Consistency applied.

[MBTcustom]

Hello, my name is Tim Malcolm. I am a custom gunsmith servicing the members of this board and the United States as a whole.
I was taught to cast by my father who was/is a bonafide rocket scientist, an avid boolit caster, and a very proficient marksman (although he is unable to do so now and lives vicariously through me.)
The first cast bullets I ever shot were H&G #34 230gr RN 45 caliber. I would whack them with a stick to knock over my GI Joes.
The first firearm I cast for was a Pedersoli Confederate Navy 44 caliber BP revolver. I mowed lawns and scraped together the money to buy it from Cabellas for $79.95 and it came with a kit. I was 14 years old at the time. I convinced my mother to drive me to the local Kings outdoor supply where I bought a Lee round ball mold. I found out real fast that COWW or COWW/Linotype (dad had plenty) were way too hard to load in my pistol, so I got some soft lead from somewhere and started casting. Little did I know that this would be the beginning of a lifetime pursuit of the silver stream. All my bullets were cast over a Coleman stove with an RCBS ladle (which I still have and use).
I ended up acquiring many different firearms over the subsequent years several of which I made myself, and casting for all of them.
I wasn’t born with a ladle in my hand, but I came pretty close.
By far, shooting cast bullets accurately in rifles has been the consistent theme of my life. It’s what I think about waking up, going to sleep, and it’s what I make a portion of my living doing. The accurate bullet is a very enticing corrot that some men will follow from the desert to the high mountains, and I’m here to tell you that I have snow in my collar, and sand in my shoes!
Those are my credentials, and who I am.

I would like to tell you how I cast excellent bullets, if you will lend an ear for a moment.
A good bullet begins with a good alloy, and an excellent bullet begins with an excellent alloy. I consider a good alloy to be small batches of COWW, or range scrap. I consider an excellent alloy to be something that you can reproduce indefinitely with a high degree of accuracy (mix of the metals) , which lends itself to consistent casting of bullets. In order to have an excellent alloy, you must have a mix that compliments itself well, and casts beautifully. Alloys that do this are Lyman#2 (90/5/5 by percent), Linotype(84/12/4 by percent), or COWW + 2.3% tin(95.6/2.2/2.2 by percent). These alloys are predictable and forgiving, which is why they are so poplar, and have been since the dawn of boolitry.
Once you have an excellent alloy, you must have an excellent mold. Excelent molds are what we do here at cast boolits. We have access to the most superb bullet molds in history, and I dare say the people of this forum are making sure to take advantage of it. (how do you know you’re a cast booliteer? When you’ll give up cigarettes so you can afford to buy custom molds every month instead! LOL!)
There are many excellent molds available today, but in my opinion, there are none who rival NOE and Accurate molds. There is simply nothing better that has ever been made in history (not even Hensley and Gibbs).
After acquiring an excellent mold and an excellent alloy, you might sit down, plug in your pot and start casting and not be very pleased with the results. You see wrinkled bullets, frosty bullets, dented bullets, and bullets with pockets in them etc etc etc.
You bought all the right tools, and the right material but you got lousy consistency.
You would like to improve on that because not only did your bullets look terrible, they shot about as pretty as they look.

The first thing to do is to take a broad stroke and change a few basic things that will put you in a good place to get started casting well. All of these things are written about at the bottom of the page in the LASC link. But just to give you the high points as I see them, here is a list of basic things you can do to get started down the straight and narrow IMHO:
1. Use a thermometer. Heat your alloy to a spot roughly 100 degrees hotter than melt temperature (that place where the lead first turns liquid and holds temperature for a while as it makes the transition).

2. Use a hotplate to warm your mold.

3. When you get ready to fill the mold, prime the spout of your pot (if using a bottom pour pot)

4. When you pour, notice where you hit the sprue hole. Some molds like the alloy to be shot straight into the hole, and some like the stream to clip the edge of the hole. Whichever you choose, try to do it the same way each time.

5. When the first cavity is filled, pile up a puddle on top of it about the size of a quarter, stop the pour, move to the next cavity and repeat.

6. Start counting “one onethousand, two onethousand” etc as soon as you shut off the stream on your last cavity filled, and watch the lead puddles on top of the mold. At a certain point, you will see them freeze over. That event needs to happen 3-4 seconds after you stopped pouring. if your sprue took more than 5 seconds to freeze, you need to slow down. If your sprue took less than 3 seconds to freeze, you need to speed up.

7. After you open the mold, look at the bullets. If they are shiny, you need to go faster. You want a nice grey appearance with sharp lines and maybe just the faintest bit of the vent lines showing as tiny dots on the sides of the bullets.

8. Use a soft faced object to open the sprue plate the very instant it freezes. You do not need to whack the snot out of it!!!! All that is required is a few sharp taps. This creates a very flat base, and does not stress your mold. My father told me to use a piece of oak dowel with a 4” piece of garden hose pushed over the business end of it. I use a small rubber hammer.

9. When you go to open the mold, do not just wrench it open. Hold it shut tight, and give the hinge bolt on the handles a good sharp rap with a rubber hammer. Be careful to hold the mold shut tight when you do this to avoid damage. Now start tapping the hinge bolt lightly as you open the mold. If any bullets stick, give the hinge bolt another good sharp rap with the rubber hammer but this time with the mold wide open so the blocks cannot clash together and cause damage (seriously, if you've never tried a rubber hammer, you don’t know what your missing. It has a kind of “jiggle” to its strike that coaxes bullets from their beds very convincingly).

10. After the bullets drop, and before you fill the mold again, there is a certain amount of time you must wait to keep your mold from getting too hot. You have to keep it consistent. Some mold/alloy combinations need 3 seconds, some need 15. It’s up to you to figure out which.

So there are the basics of how to cast good bullets. That’s a lot of info and is about like trying to ride a bike while playing the violin till you do it a few thousand times, but what if you've got that all down pat, and you’re still not happy with the results?
Allow me to show you a method that I developed with help from sgt.mike, by which you can refine the above information to an exact process.
I use bell curves to teach me where I need work, and when I make a change, to show me whether or not it was a positive change, and it works exceedingly well for this purpose.
What’s a bell curve you might ask? It’s simply a way to use your digital scale to plot your proficiency, and literally plot it with the bullets you cast.
Here is an example:
(Can't attach any more photos. See the bottom of the post.)
This is done by simply lining up all the bullets of a certain weight in a row, in .1gr increments. It’s easy to do and teaches you faster than anything else I have ever tried. I wish I had thought of this years ago, because I wasted a lot of time not getting instant feedback from my pot. As they say, I was “close but no cigar”. It turns out that almost any defect in size, shape, mass, or diameter of your bullet can be sensed by our ultra-precision digital scales. Feel free to test this. Take a bullet and put it on your scale. Tare the scale to the bullet. Now file just a little bit off the nose and see how much it takes to make your scale read -.1gr. Like I said, it really doesn’t take much.
The only thing the scale can’t detect is the appearance of your bullets. Everything else has an effect on the weight. That’s why I pay attention to bullet weight first and foremost, after learning how to cast a good looking bullet with no wrinkles, sharp bands, flat bases, clean noses, good manners, and winning personalities. Applied to an entire batch of bullets, and in turn, several batches of bullets from the same mold and alloy in comparison with each other, the scale is able to tell you how consistent you are on a very basic level. The scale doesn’t care what the defect is, it will see it. It may miss a bullet because that bullet is so jacked up that it has contradictory flaws that fool the scale, but the chances of that bullet previously making it out of the mold unnoticed by you for any defect of appearance,( and also being the only one in the whole batch) is almost impossible. Observing proper casting technique as taught on this forum takes care of 98% of the inconsistencies you have in your process just by observing and following a process that applies to all molds equally. But, this process is specific to each mold you have and while some of your technique will apply to different molds equally, you can be sure that each mold will have a personality of its own, and this technique will dial you into it very quickly.
The way you use bell curves to teach you is to use them to dial in each of the steps listed above that have an effect on bullet mass or physical fitness. (don’t worry, you’ll be taking the good ones and shooting them as you go along. This is a long term project that will take many casting sessions to perfect.)
What you do is use your normal method to cast 100 bullets (I personally find this to be a minimum for any sort of a telling bell curve) and line them up based on bullet weight with each row representing .1gr increment of your proficiency.
Do not cull any bullets as you do this. This is the time for truth and brutal honesty, not looking good on paper. It’s not a measure of you it’s a measure of your technique.
Once you have all your bullets lined up, take a picture of the result, or use a pencil to outline the shape of the bullets on the paper and record what your spread was.
At this point, you may look at the brutal honesty of the bell curve before you, and postulate an opinion about why it’s bigger than you thought it would be (and I can almost guarantee it’s not going to be as perfect as your thought). You say “oh well, that was because I waited too long between fills. It’s just not my best run is all.”
Go back to your pot and cast another 100 bullets having corrected what you thought was wrong. Plot them again and see if you were right. (Remember: Brutal honesty. No matter how badly you want to scrape the corners off the base of the Christmas tree, you must not, or you are only fooling yourself. Those defects are trying to tell you something!)
After you have tried what you said, and it really didn’t make the change you thought it would, you’re going to get frustrated. May I suggest you try going right down the list above and choose to explore each variable? It’s time consuming, but I found it to be very fun, and each bell curve teaches you things, and there will be many “light bulb moments”.
Lets just walk through the casting principles I listed above and I’ll show you how to measure a few of them. There is a lot to learn and it’s the coolest thing in the world to find things you thought were your problem were not, and other things you thought didn't matter actually do!
1.Alloy temperature. Change your pot temperature 25 degrees at a time and plot bell curves. Keep the best one.
2.Prime the spout of the pot. If you don’t, I would challenge you to do so and observe the change in your spreads. I went as far as to witness each cavity of my mold and separate the good bullets (+- .2 grains) by cavity they dropped from. Turns out, cavities 1 and 2 were always lighter than cavities 3 and four because cooler alloy is thicker than hot alloy, and that was how much lead it took to stop the nozzle from changing the alloy temperature. Once I started priming the spout for a whole second, the variation between cavities disappeared.
3.Stream location in the sprue hole. This is cool. If you do not take care to hit the sprue hole consistently, then do so, and see the difference. If you throw the lead straight down the hole, then do it every time, or clip the edge of the hole a certain amount, and do it every time. Plot a curve, try something else, and plot again. You’ll be surprised such a little thing makes such a difference in your brutally honest bell curve.
4.Puddle size. Try different size puddles and observe the difference.
5.Puddle freeze time. This is a big one that will show a difference. Try running hot enough for a 3 second freeze, and try running hot enough for a 5 second freeze, and observe the result in the bell curve.
6.Dwell time. After dumping the bullets, we wait a certain amount of time. But it’s just a wild flying guess how much based on what happens several steps later. I suspect that most of the time, we end up running just a little proud or a little shy of where the mold wants with that alloy at that temperature. We go back in just a little too soon, and see the puddle takes longer to freeze, so we wait a little bit longer than usual on the flip side, and hope it works etc etc etc. Well, the bell curve sees that variance when you plot. The fact that you were not dwelling the correct amount of time means that you’re always going to be chasing rainbows unless you test what the correct dwell time is and stick to it like glue. If you fill too soon, then dump the batch and quit doing that!

This is very simple, use bell curve comparison to dial in your process to perfection. This is just like going to the eye doctor and he has you compare prescriptions with his expensive machine. He doesn't choose your prescription you do. He depends on your brutally honest comparison of “better or worse” to quickly find your prescription out of about 1000 options. Because each test gets you better and better, the final result represents the limit of what the available technology can give you. That’s exactly what I’m proposing here. Each mold has a “prescription” that will make it focus your effort better and you just need to run a few tests to determine what it is.
What if your eye doctor ran his business like we usually cast our bullets? I think it would be something like this:
You walk in and tell him you need a pair of glasses because you can’t focus.
He tosses a used pair of glasses across the counter and says, “these here worked for me when I was your age. That’ll be $150.99.”
You try them on and inform him that they’re better, but not really as good as you had hoped.
He says, “Don’t be silly! You have to wear them for at least 6 months before you can tell whether they work or not!”
That’s about how it is with cast boolits. The first thing you have to do is learn to see and that involves following the steps provided, but after you learn to see you must learn to focus. And focus is not a one size fits all proposition. It’s a very personal thing that you must learn for yourself and about yourself in order to be effective. It’s easy to paint with a broad brush and say that everybody does the same thing, but when you get down to the details, you find that casting good bullets is as personal a thing as a pair of shoes, or glasses. Each person does it slightly different.
I teach people to cast very often here at the shop (if you want to swing by, Sunday is casting day and I don’t charge a thing.) and I have learned not to bust on people when they do something different than I do. As long as it works for them, its fair play, and I love seeing the diversity of style (sometimes I even learn something myself! LOL!) I encourage people to develop their own style, but not at the expense of precision and consistency.

Now, one thing I would like to say about this is that if you want absolute perfection, you are going to have to run back through and retest each variable I mentioned (and any that you change) the reason being that these things are all connected, and when you change one, you change the others slightly too. However, if you keep whipping your process with bell curves, you will get more and more consistent and more and more focused till you can cast with proficiency that is absolutely astounding. (My personal goal is 299 good one out of a 300 bullet session.) I have been doing this for a year now, and it’s getting better all the time.
This was my last run:
340 bullets cast. 299 good ones that weigh 0.0 on a tarred digital scale, and 41 bad that weigh anything but 0.0 and only one that was lighter than 1gr. I’m going back over my process each time I cast and looking to improve myself.
This is a progression of my improvement so you can see how this has worked for me, ending with the example I just gave. Some of these curves are not 100 each, and some are more than. The determination that 100 minimum is a recent conclusion of mine.
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131541
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131543
BTW, you find a light bullet, its probably a void:
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Again, what you see in the orange tote is 299 bullets that weigh 0.0 on a tared scale. All those on the paper towel are the ones that did not weigh 0.0 and would be clustered around the bottom of a looooooong line of good ones if I plotted them into a bell curve. That's the best I have don'e so far.
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Like I always say, it’s not the only way, but it’s a way that might work for you. Feel free to try it and use it to improve yourself.

Thank you.

[waksupi]

Good post.

[Yodogsandman]

Tim, thanks for your very informative thread!

[Larry Gibson]

Excellentdissertation goodsteel.

I can only add that I generally cast with two basic methods; quantity orquality.

When I am casting for quantity with single through 6 cavity moulds the goal is useablecast bullets for close range handgun or plinking where "best"accuracy is not the primary requirement. By useable cast bullets Imean bullets that may be partially frosted, shiny, not all of the same"as cast" diameter, maybe even a wrinkle or twos as long as the basediameter isn't compromised. When shooting fast multiple shots on largertargets (silhouette defensive targets, dingers and even steel SASStargets) let’s face it; top quality cast bullets are not really needed. Whenshooting low velocity plinking loads with handguns or rifles at rocks, dirtclods, pine cones and cow pies best quality cast bullets aren't really neededeither. Here useable cast bullets are had with a wide range of alloys(mostly scrounged range alloy with additional lead and tin added) cast atvarying alloy temperatures without too much fuss. I do not weight sortand mostly give only a cursory examination when sizing or loading to ensure thebullets is "useable". Lots of fun can be had with those kind ofloads and little pain or frustration when casting and loading. I might note that with a little attention,proper casting tempo, a quality alloy that casts well some pretty good bulletscan result given some good accuracy even at 100 yards when casting forquantity, especially if you simply cull the ones with visual defects out. I shoot a lot of these type cast bullets.

However, when I want to shoot cast bullets for hunting, target shooting (wherescoring is done), accuracy testing with rifle or handgun and especially whenshooting high velocity in rifles then when I cast things slow down and I castfor quality. Quality meaning the best and most consistent in weight andas cast measurements as I possibly can. When casting such even withmultiple cavity moulds I pay careful attention to most all the detailsgoodsteel discusses. In doing such for many years casting literally thousands (inthe last 2 days I have cast over a thousand 30 XCB bullets of linotype) I havefound that each alloy has a specific small range of temperature when used whilecasting is where I get the most consistent bullets. Using that specific temperature range for theparticular alloy gives less rejects due to defects in the cast bullets. These are discovered by a close visualexamination for external defects and weight sorting for internal defects.

I get reallyanal about weight sorting, especially for high velocity rifle cast bullet use.I have found through much HV testing that a +/- variation of .2 gr with 150 –165 gr .30 caliber cast bullets is sufficient for the velocities I am pushingthese bullets to. I have found no discernible difference in accuracy at theacceleration rates, psi’s and velocities I use between cast bullets of exactlythe same weight and those having the .2 gr +/- weight range. Weight sorting by .1 gr will give the “bellcurve” and demonstrate where this is for each bullet and alloy.

If the alloy isthe same, the mould the same, the casting technique the same and the alloytemperature is maintained in the sweet spot range then the external dimensionsof the cast bullets are going to be as close as you can get them, especiallywhen cast in different sessions on different days. I cast 436 XCBs day before yesterday and over700 yesterday. Thus far weight sortingis producing the same bell curve for both days of 154.5 gr +/- .2 gr. Measurements of the 30 XCBs from both days thusfar on a comparator are showing no variations between the cavities and novariation between the days casting. Alloyused was straight linotype and I found the sweet spot at 725 – 740 degrees usinga Lyman casting thermometer. I keep thethermometer in the alloy in the Lyman Mag 20 during casting for constantmonitoring.

Quality castbullets demand that consistency be applied consistently. Excellent post again goodsteel and I also recommend this be a "sticky".

Larry Gibson

[TXGunNut]

Thanks for investing the keystrokes, Tim. I've been using that bell curve evaluation method for a few years, it's one of the best reasons for having a digital scale. For a real eye-opener use that same method with commercial j-words.

[MBTcustom]

Another thing this method has taught me is the absolutely stagering level of precision that as available from our custom mold makers. For instance, I too have found that 730 degrees is the sweet spot for alloy temperature using Linotype in my brass 2 cavity XCB mold. The bullets weigh 154.8.
sgt.mike came by last night to show off his new aluminum 5 cavity XCB mold. I was not surprised to find that once we dialed in the casting cadence, it too dropped bullets that weigh exactly 154.8 grains. We are obviously using our casting method to realize the precision that the mold maker designed into the product.
This is a relatively recent development that is made possible by CNC interpolative machining, and CNC micro lathe boring. Back in the early days of cast boolit molds, each cavity was a fingerprint and would cast it's own way, so the common practice for competition was to use single cavity molds. I can tell you that with the modern molds we have available to us, if you match your process to the mold, it is very possible to get superb results out of a mold with many cavities, which is a huge boon to the cast bullet shooter.
I originally started witnessing mold cavities back when all I had were cherry cut, two cavity, cast iron molds, and I never found one that dropped identical bullets from both holes until I tried molds made by our custom makers. If there is any difference at all, it's so minute that nothing I have in my possession is capable of measuring it (and measuring things is kind of what I do).
No indeed. If I find a cavity that will not cast immeasurably the same as the others with a custom mold, it is much more likely that the problem lies on this side of the hinge bolt. Trust me, when I say "this level of precision impresses me" I am speaking from the perspective of a trained aerospace machinist, tool and die maker, and gunsmith.
However, for all the precision that has been included in our custom molds, I believe that less than 1% of bullet casters actually try to find a way to utilize that precision to the limit that our tools will allow, and I have started this thread in an effort to convince people to make the attempt, and possibly to give people a small taste of what is possible if you learn to use these tools to achieve levels of consistency that have only recently been even remotely possible.

There is a sweet spot in temperature, cadence, and dwell time that if found is as reliable as the sunrise. If this sweet spot is found and realized, you can make superb casting runs where 90% of what falls from your mold is actually matchgrade product. A little work up front with a scale pays off at the range, and on your targets.

Using this process helps you achieve excellence no matter what method you follow, and the results can be better than you ever thought possible.

Thank you.

[Blackwater]

That's as good a tutorial as I've ever read anywhere. Thanks. I know many new casters will be helped greatly if they'll just print it out and memorize it. Lots of good and true principles there that we see argued pro and con regularly. I really like the way you point out how when you cheat on one end, you pay on the other. We "moderns" seem to always be in a hurry, and we seem very resistant to accepting the simple fact that sometimes, things take as long as they take, and just can't be rushed no matter how much we'd like them to be. Good post.

[TXGunNut]

All I can add is something that should go without saying; when I find the cadence and temp that a mould likes I write it down. I've added a separate page to each cartridge section of my "load notes" book for "casting notes" so that I don't have to start over again next time I pick up that mould.

[milkman]

Another excellent post in a long line of excellent posts. Thanks for taking the time to share. I have a question though--- will a really high quality boolit make the rifle quit shaking while I'm trying to aim?

[tmc-okc]

Tim, Thank you. Your explanation and instructions are not lost on me. I have printed and laminated your instructions and they know reside taped to the wall on the left side of my casting furnace ( I can read it better there thru my $29.95 Walgreens reading glasses). I have yet to cast my first boolit but I have "smelted" about 300 Lbs of COWW and have about 100 Lbs of pure lead to cast into ingots. I am now on my way to Harbor Freight to purchase a rubber hammer. Gotta pickup a digital scale that reads in Grains somewhere. I guess I could use my powder scale but I believe that would be slow and tedious and not sure it would provide the results I really want.

Thanks again.
Your efforts are not wasted on some of us.

[MBTcustom]

Another excellent post in a long line of excellent posts. Thanks for taking the time to share. I have a question though--- will a really high quality boolit make the rifle quit shaking while I'm trying to aim?

All I'll say is that absolute confidence in the quality of your equipment, (like a forgone conclusion), can have a powerful effect at the moment of truth. If you wait to think about this stuff until you miss two deer in a row (or worse, "almost miss") or until you are trying to prove your load's worth in competition, it's too late. I don't like depending on a run of bullets that just "came together for me on that one day that I wrote on the calendar" and loads in which their effectiveness is balanced on the head of a pin.
If I can't step up to the pot and call my shot, there's no reason I should expect to step into the woods or up to the line and do any better.

However, if you have based your loads on facts, and solid science, and your casting runs are built on the same foundations, then you know that even when you're having a bad day, the work you did in preparation will carry the burden of performance. That goes for casting, loading, and shooting.

[Larry Gibson]

As mentioned in an earlier post I had cast about 700 XCB bullets of linotype yesterday. I sorted for any visual defect and by weight today. Also as mentioned if one is consistent in the techniques covered by the OP in this thread the bullets cast today can be the same as those cast several days or even months ago. Those I had cast last Friday for high velocity use in the 30x60 XCB were weight sorted to 154.5 gr +/- .2 gr. And so it was with those 30 XCB bullets s cast yesterday. I had used the same linotype alloy, monitored and maintained the alloy temperature at the “sweet spot” of 725 – 740 degrees with a casting thermometer in the alloy and used the same casting tempo and technique as before. I ended up yesterday with an estimated 700 bullets.

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I didn’t miss that guestimate by much as there were 673 XCBs in that pile. Weight sorting them and visually inspecting them resulted in 13% (89) being rejected for weighing less than 154.0 gr or for any visual defect. At the bottom end a small lot of 6% (44) weighed 154.0 – 154.2 gr and will be used in the Palma rifle with 14” twist. At the top end 11% (76) weighed heavy at 154.8 – 155.5 gr and they will be used in my M70 ’06 with 10” twist. In the middle, the so called dome of the bell curve, there was 70% (464) that weighed in at 154.3 – 154.7 for a nominal 154.5 gr +/- .2 gr…..the same as those cast last Friday. The five smaller cups in the middle are the 464. The left cup is the culls, the right cup the "heavies" and the front cup is the light weight bullets.

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Thus out of yesterdays casting session I ended up with 87% shootable 30 XCB bullets. Both days give me 800+ 30 XCB bullets suitable for high velocity in Dawn, my 30x60 XCB rifle. My first outing with these bullets will be testing the 30 XCB bullet cast of linotype at 2950 – 3100+ fps. Hopefully will get to shoot on Monday orTuesday and have a report to post on the “Slow Twist…..” thread.

We see that consistency applied correctly does indeed pay dividends.

Larry Gibson

[ascast]

Excellent post, so now do you shoot those in order? (lol) Someone mentioned talking down notes, which is a MUST.
Also, what kind of music your playing. Music tempo can really foul things ups.

[prs]

Thank you to Goodsteel and also to the commenting posters in follow-up. Goodsteele, your first pic caught me off guard as the bell curves I construct and have used in the past in other applications had greater weight or quantity to the right and lesser to the left, but so long as you don't break into SDs and such I can hang with it. You mentioned casting in a shop and that can be one HUGE variable, the ambient temperature being, well, consistent. Those of us casting more in the open areas contend with re-learning freeze and dwell times as well as rate. Thanks again!

prs

[bhl2506]

A big thank you from an infrequent poster. Always a pleasure to read your post goodsteel! This entire post has been down loaded an printed out. Thank you again!

[MBTcustom]

A big thank you from an infrequent poster. Always a pleasure to read your post goodsteel! This entire post has been down loaded an printed out. Thank you again!

My pleasure sir.

[detox]

A nice even, unraised, untorn sprue cut is a must also. Raised cut is not good. Torn causes unwanted voids.

[leeggen]

Mr. Goodsteel again I am impressed by the knowledge and sharing of such on this sight. I don't know how others feel but maybe this should become a "sticky". Thanks for sharing.
CD

[MBTcustom]

Great demonstration Sarge. Thank you for weighing in sir! (pun intended) LOL!

[Larry Gibson]

Mike

Interesting to note your "G2" cast 30 XCBs are averaging out identical to mine from my last 2 casting sessions as I posted above! Obviously "consistency applied" is practiced extremely well in the making of moulds at NOE:castmine:

Larry Gibson

[NC_JEFF]

Thanks for this thread. I'm posting it in my caring notes asap, right inside the front cover.

JD

[MBTcustom]

This is the method I use Mike. LOL!
This is a casting session using Linotype. I quite three times to yak at people on the phone in the middle of this. There are no culls. This is the whole run, and I just finished about an hour ago.
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I think I'll throw those seven stragglers back in the pot.

Now, I can get pretty close to this consistancy with any alloy in my possesion, but if I do anything different, if I move ten degrees off with either the mold temperature or the alloy temperature, if I dwell ten seconds longer or slower, the base of the bell curve gets wider, and there is nothing that will stop it from doing so.
Now granted, it may only add 10 bullets to the duds, but you have to figure that when you increase the inconsistency of your bullets, you increase the odds that one of the ones you kept will be off balance, or damaged in some way that you cannot measure except with points lost, targets missed, or groups blown.

In this case,
I was using a PID controller on my Lee Pot
I had an NOE temperature gauge on my mold (awesome tool to improve consistency BTW)
and I had a timex watch laying right between the hot plate and the lead pot.
A couple days ago, I used this method to systematically pin point each part of the equation, and today, I walked up and did this.

Pot was at 740 degrees.
Mold was at 383 to 388 degrees and the hot plate was adjusted to maintain that temperature.
Cadence was exactly one minute per pour. Filled at 0, cut at 23, dropped at 27, shut at 30, paused for 30, and repeat.
Spout was primed for one second.
Alloy was started in the sprue hole by clipping the far edge of the hole, centering smoothly, and clipping the near edge as the pour was finished, and the puddle was about the size of a nickel:
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Not a bad way to make a deal with a Lee pot for precision.

[detox]

I try to cast with two cavity mold only and separate bullets by cavity. Then weigh and bag bullets from each cavity.

I like casting with simple Linotype, but Magnum birdshot will cut cleaner at base of bullet without voids. I must cast HOT to get good fillout like linotype. The arsenic in birdshot will help get bullets super hard when heat treating. Super hard is needed for high velocity. Linotype is not hard enough.

[MBTcustom]

I try to cast with two cavity mold only and separate bullets by cavity. Then weigh and bag bullets from each cavity.

I like casting with simple Linotype, but Magnum birdshot will cut cleaner at base of bullet without voids. I must cast HOT to get good fillout like linotype. The arsenic in birdshot will help get bullets super hard when heat treating. Super hard is needed for high velocity. Linotype is not hard enough.

Indeed so. It's a misconception that Linotype is hard as diamonds. It's only 22BHN! Now the stuff is brittle, but only past a certain point, and only in a "tensile strength" way. The alloy actually engraves like butter.
I suppose that's why Larry and Bjorn have been able to break 2950 and 3100 FPS (with accuracy) using that alloy.

[detox]

Adding linotype makes a lighter weight bullet. Not good for long range accuracy.

[MBTcustom]

Adding linotype makes a lighter weight bullet. Not good for long range accuracy.

This thread is focused more on accuracy at the bench that can be used on the range as the situation calls for it. So far, I have demonstrated casting consistency here with three different alloys (50/50, 95.6/2.2/2.2, and Linotype). I have also created bell curves for Lyman #2, and COWW.
The bullets from each of these were consistent, and now that they have been rendered perfect in shape, size and weight, they can be heat treated, or annealed to my pleasure, and tested in the same scientific manner on the range to determine what works and what we only wish (or thought) would. No range test can be relied on though, if consistent bullets are not being used to perform that test.
This latest example just happened to be Linotype. That doesn't mean it's what I think is the answer to all my casting needs. If there were an alloy that I would attempt to put into that narrow and confined slot, it would be COWW+2%.

[Hannibal]

I'd like to add another vote for *sticky* status. This is good stuff here.

As for results, well, I've definately learned something here. It's going to take another casting session or 2 to sort out just what though. :veryconfu

[cbrick]

Actually Detox I debated that (birdshot mixed with Lino as the arsenic would allow heat treating)

It's antimony that allows heat treating in common bullet alloys. Any Pb/Sb alloy can be heat treated for additional strength. Arsenic (As) will act as a grain refiner in a Pb/Sb/As alloy and result in a higher BHN than binary Pb/Sb. To say that As allows heat treating is incorrect and in effect is saying that heat treating cannot be done without it.

Rick

[Jevyod]

Excuse my ignorance, but what do you mean by prime the spout? I have never read about this before???!!!:confused:

BTW excellent post Tim! Can't wait to apply that when casting for my 358!! I also vote "sticky"

[Bjornb]

You prime the spout by opening it for a very short amount of time (maybe 1 second) and dropping the lead on the sprue plate and not in the hole. This ensures that the lead going into the cavities is all of a uniform temperature, since the lead sitting in the spout between pours will be slightly colder that the main contents of your pot. A small detail, but it adds up to consistency with all the other small details.

[prs]

[QUOTE=cbrick;3150887]It's antimony that allows heat treating in common bullet alloys. Any Pb/Sb alloy can be heat treated for additional strength. Arsenic (As) will act as a grain refiner in a Pb/Sb/As alloy and result in a higher BHN than binary Pb/Sb. To say that As allows heat treating is incorrect and in effect is saying that heat treating cannot be done without it.

A trace of arsenic is a wonderful catalyst in the quenching of lead alloyed with equal adjuncts of Sb and Sn. I believe you can refer to the Lyman Cast Bullet edition just prior to the current edition. It seems that most lead has a trace of arsenic in it like it or not, but I am not sure of that.

prs

[MBTcustom]

I have a ladle resting under the spout of my pot, and below the block shelf. Before I put the mold under the spout, I run a 1 second stream into the ladle. This heats the spout and insures that the cool alloy in and above it, is cleared.
Immediately after shutting off the stream, the mold is placed under the spout and the first cavity is filled, the stream is stopped, the second cavity is filled, the stream is stopped, etc etc etc.
This was the single biggest thing that brought multiple peaks in my bell curves into one single peak.
Here are the two curves that I used a year ago to learn this:
131863
131864
Obviously, at this time, there was still a lot of things I was doing wrong that made my consistency rather shoddy, but you can also see how making that one change actually had an observable effect on the bell curve. I never could have seen it otherwise.
That's the greatness of this method. It's not all clear, or all fuzzy. Using the bell curves to improve your casting is simply a fuzzy picture that gets more focused or less as you make changes. This is why I used the example of the eye doctor trying different things and relying on your simple answer of "better or worse" to dial in an exact prescription out of a staggering number of variables. We are doing the same thing, and this method allows you to see instantly if what you just did different was "better or worse".

[buckwheatpaul]

Great post expecially for new casters and older caster that have been out of the casting business for a while.....THANKS!

[MBTcustom]

The problem with weight sampling - you don't know if it is a deformity or just a larger dia. boolit.

I would prefer to have neither.
When you cast 300 bullets and have less than 1% variance in weight, and all of them look superb, it is a fairly safe assumption that most of the bullets in that narrow .3 grain spread are identical in more ways than not.
However, that is a much shakier assumption if 25% of your bullets miss that narrow field of acceptance.
That said, if you believe that a large bell curve such as demonstrated in the OP will shoot just as consistently as those in a small bell curve such as I just posted, then your opinion will be either validated or invalidated by your targets and what you are trying to achieve.
For instance, if all I was concerned with is putting five shots into a 2" group at 100 yards (which really is not all that bad of a group) at normal CB velocities, then none of this would appear to make any difference to me. But if you want to shoot 20 shots into a 1" group at 100 yards at 2700 FPS (my personal goal) then you might find that using this system is one way to get you there as it pertains to your bullet casting.

The weight itself is not the issue. I think that if weight were all we were concerned with, then anything in a 2 grain spread would impact very close together downrange. But I'm not measureing weight for weights sake alone. If that were the case there would be no reason for the bell curve. Rather, I am using the bell curve to plot the weights of the entire casting session and using it to determine if I am achieving consistency as it pertains to the variables I have control over (I'm really not concerned with the variables I do not have control over except to attempt to overcome them with the variables that I do have control over).
Because it is a scientific fact that if any part of the mass of the bullet is changed, it will have a direct effect on the weight of that object, and since the shape of the object is set by the precision mold we are using, the only way the weight can possibly change is by being either more or less massive with the same shape, or harboring a void within the object, or a combination of the three.
The voids are the main thing I want to eliminate, but the problem with them is that they cause such a minute change in the weight of the bullets that they are easily hidden in the inconsistent weight of the bullet. Therefore, I concluded that I would eliminate the variances in weight of the bullets, and improve the consistency of my bullets to the point that I could observe a void in the bullets with a scale and that is what I have done in a nutshell.

If you think about it, the only way that bullet could become truly imbalanced is if there is a void present.
Based on the consistency that I am achieving now (rivaling jacketed bullet consistency) I feel very confident that the scale is not only telling me that my bullets are the same weight; its also telling me that my bullets are the same diameter, the same length, the same shape, and they are balanced as well.


That said, I confess I have not attempted to intentionally cast in a way that I now consider substandard to see if my groups open back up to where they were before I developed this method.
I assume that to be the case, and honestly I see no reason to use bullets that are horribly inconsistent in weight (and who knows what else) if I have the knowledge of how to cast better, which I do.
I have fully disclosed how I achieved this level of accuracy and consistency so that those who have a desire to shoot excellent bullets in their rifles have the knowledge of how to do so.

Thank you.

[Jevyod]

Not sure if this is a dumb question or not. If it is, I apologize! How much difference does ambient temp make a difference? Say I cast in the summer, with temps around 80. I get everything figured out, and discover that I need 20 seconds for the sprue to freeze, then a wait of 25 seconds before refilling. Now say I kept all the records, and wanted to cast in the fall with temps around 50. (unheated shop) Can I go by what I did before with warmer temps, or will I have to start over. In other words, do I need records for different temp variations in my shop, or not? Hope this makes sense....

[cbrick]

Not sure if this is a dumb question or not. If it is, I apologize! How much difference does ambient temp make a difference? Say I cast in the summer, with temps around 80. I get everything figured out, and discover that I need 20 seconds for the sprue to freeze, then a wait of 25 seconds before refilling. Now say I kept all the records, and wanted to cast in the fall with temps around 50. (unheated shop) Can I go by what I did before with warmer temps, or will I have to start over. In other words, do I need records for different temp variations in my shop, or not? Hope this makes sense....

Not a dumb question at all. You can keep the alloy in the pot at the same temp easy enough but the air temp your casting in will have a profound effect on mold cooling between pours and even if the mold can get or stay at proper casting temp if it's cold enough air temp. Mold temp consistency or lack of has a profound effect on bullet weight consistency during a casting session and in different casting sessions. So actually that's a good question.

Rick

[MBTcustom]

Not sure if this is a dumb question or not. If it is, I apologize! How much difference does ambient temp make a difference? Say I cast in the summer, with temps around 80. I get everything figured out, and discover that I need 20 seconds for the sprue to freeze, then a wait of 25 seconds before refilling. Now say I kept all the records, and wanted to cast in the fall with temps around 50. (unheated shop) Can I go by what I did before with warmer temps, or will I have to start over. In other words, do I need records for different temp variations in my shop, or not? Hope this makes sense....

Watch your puddle freeze time and the color of your bullets etc etc. They will guide you in no matter what the ambient temperature is. However, you may have to adjust some of the other things to get perfect consistency back.

[btroj]

Wow, cleaned up and reopened already.

[btroj]

Even the accuracy gurus at the CBA aren't in agreement on the need to weigh sort. They might be on to something.

Have you posted this over there to see what they say?

[MBTcustom]

Even the accuracy gurus at the CBA aren't in agreement on the need to weigh sort. They might be on to something.

Have you posted this over there to see what they say?

Once you know where to run and have written down how your mold prefers to be run, it's no longer necessary (which was the reason for me starting the original thread if you'll remember).
If you know where your mold likes to run, for 99.9% of the shooting we do, you can rest assured that what drops from your mold is usable product with no discrepancies. Like that last run I made for instance. I would gladly shoot every one of the bullets in that bell curve without a second thought if I were shooting well below the RPMTH and going for low speed solid accuracy. There were only 7 that missed the target consistency of +-.1 grains, and since those seven were so close to target, I feel very sure there is very little wrong with them.

I'm not recommending using a scale to find the faults in your bullets (although plenty of faults will be seen), I'm recommending using the scale to find the faults in your method and process. Given a little time, it works very very well to that end and I benefited greatly from it in 2014 and so did several other people I told about it, and who helped me develop it (like sgt.mike).
In fact, it worked so well for everyone involved, I thought it might just be a benefit to someone here on the forum. I have tried to word it as clearly and thoroughly as my vocabulary will allow.
So now we have come full circle, right back to where I started the previous thread. Everybody is up to date, and now that the back story is filled in, I am hoping that this will be helpful to everybody concerned.

(edit to add) Maybe now my original thread will make more sense if you read the OP:
http://castboolits.gunloads.com/showthread.php?269367-Consistency-applied

Thank you.

[MBTcustom]

OK, so back to consistency.
I want to take a minute and talk about a tool I have just started using a few months ago. That would be the NOE mold block thermometer.
131921
I got this neat little unit from NOE bullet molds.
When I first started using it, I really couldn't tell that it was much use at all for telling me where to run my molds temperature. It turns out, I absolutely did not understand how this tool was to be used!
I decided to give it another shot, now that I have my process dialed into perfection using the bell curves as a training aid. I just plugged it in, and started observing what the thermometer would tell me. At first, there really wasn't much to see. The temperature would dip down about 5 degrees when the mold was shot full of alloy, and then it would raise five degrees after I dropped my bullets (there's a lag time between when you fill the mold and when that heat flows down to the probe in the bottom of the mold.)
No great shakes, I saw nothing really exciting. Until I needed a break and I put my mold back on the hotplate.
When I returned from whatever I was doing 15-20 minutes later, I saw that the temperature had dropped about 25 degrees low. "Huh. Interesting." I thought. "lets see how many pours it takes to get back up to the right temperature running at my normal cadence."
10-15 cycles later, it was finally back up to temperature.
"Interesting" I thought.
The next time, I turned my hot plate up higher by a little bit (just guessing).
When I returned from my break, the mold was 25 degrees hotter than when I left it.
"Huh." I thought. "lets see how many pours it takes to get back down to where it's supposed to be this time".
3-4 cycles later, I was back where I needed to be.
"Interesting." I thought.
I went along my merry way then casting along just as easy as you please, and then the phone rang. I answered it and stuck in my earbuds real quick and tried to do like Mrs. goodsteel and carry on a conversation while I was working. Unfortunately, I am not gifted with the ability to multitask like my beloved counterpart and I ended up missing a few cycles and the mold got cool. It took nearly 10 cycles to bring that mold up to temperature, jacking with the dwell time, and trying to control the sprue freeze time and talk about gunsmithing all at once!!!!
I ended up putting the mold back on the hotplate, and I was glad I dropped all those bullets on the bench while I was trying to get my mold back up to temperature.
When I picked it up off the hotplate, it was back about 20 degrees hotter than it should have been, and I was quickly back in business.

The moral of the story is a very important lesson that you can use even if you don't have all the fancy gadgetry that I have:
When you set you hot plate, just make sure that it is set hotter than it needs to be. When you start casting, just jump right into your preferred cadence and stick to it like glue, and drop the first 5 fills on the bench, or in your sprue pan or what have you, then just start dropping them in the bucket as if you had been doing so all along.
If at any point, you mess up, and suspect that your mold got cool, remember that pouring bullets will waste more time and alloy in the long run, than if you had just taken the opportunity to set the mold aside and stretch for a minute or ten.

Also, I want to tell you about a trick that I got from our very own Lars45 last time I was out at his place. I told him I have always had trouble getting dinged up bullets when I water drop, because they hit each other under water. I have tried the rag over the bucket with a hole cut in it, but that's a PITB, and I always end up using the rag for wiping a machine down or something when the pot is not in use. Also, I still get dinged up bullets when I use that method.
He told me to try floating sponges on top of the water and try to hit them with the bullets when I drop.
Fortunately for me, mrs.goodsteel had just recently bought a package of six dish sponges and I took the liberty of commandeering them for the cause (well almost six, shes getting smart, and had hidden one from me. LOL!)
131922
This worked absolutely perfect. The bullets came out cleaner and prettier than ever, with nary a ding one.
Really good trick!!!

[MBTcustom]

In case you hadn't noticed, consistent casting is all about temperature and timing, and if you control these things, you're going to be able to drop absolutely stuningly beutiful and consistent bullets session to session like clockwork.
Speaking of clockwork, let me show you what I use to control my cadence, time my sprue freeze etc etc.
If I can divide the cycle in 15, 30, 45, or 60 second increments, I much prefer to use my trusty Timex.
131923
It works very well for casting because it is so large, it's easy to see.

Unfortunately, often the temperature falls somewhere in between a 15 second increment in order to be just perfect, so I have a small digital egg timer I got at Walmart for situations like that.
131925
Once set, it will count down the time to an alarm when the "start/stop" button is pressed.
I use this by setting it so that when it beeps, I fill the mold, and as soon as the puddle freezes, I start it again and cut the sprue, empty the mold, shut the mold, wait for the beep, and repeat.
This actually works quite well, although after hearing that beep about 200 times (and you with a rubber mallet in your hand the entire time) you really have to resist the urge to smash it to pieces by the time you're finished (price we pay for precision).

The nice part about it is that you can lay it flat on the bench and press the button (even with a gloved hand) and you can keep your eyes on what you are doing, instead of on a watch face.
I'm always looking to improve on this particular tool, so if anybody uses something like this that's a little less annoying, "I'm all ears" .

The important thing is that since temperature and timing is the name of the game with consistent casting, you need to find a way to measure/control these two things, and the more you do, the better your results will be.

One of the best parts of controlling these variables and knowing what works, is that it actually takes a considerable amount of pressure off you as the caster. You can get up and stretch, kiss the wife, spank the kid, kick the dog, answer the phone, smoke, spit, go to the washroom, or all of the above that a normal human needs to do from time to time, and in the midst of all that chaos, you can create perfectly consistent bullets all day long. (to say nothing of the fact that sometimes you need to add alloy to your pot and that takes some time to right itself.)

[Hannibal]

Rick casted some tonight with a differant alloy ( which I need to get XRF'd I forgot what it was ) to see just how it would run.
Well you know we have the weird snow and cold that is seasonally unusual I was in my shop casting the shop is uninsulated no heat cept the hot plate and lead pot. Little cool to say the least
as I was using beewax to "refine" the alloy I had the door open. The wind was messing with the mold pretty badly I had 1.4 gr variance in the bell curve.

Thinking that I need to drop the temp in the pot a bit. And pick a bit warmer day.... LOL I was able to save quite a bit though for mid-range velocity.

Thank you for posting this. I've just had another 'Ah, Haa! ' moment.

[MBTcustom]

Just a word on fluxing.

There is great debate about this issue, and I don't care to have one here. This is just what I do to get consistency (as described by the bell curves posted earlier).
Sawdust is the greatest flux ever discovered, and I give Glen Fryxel full props for his recommendation of it (although for the record, my father recommended it to me back in the early 90s as well)
If there exists some goo or some stuff that burns that can be thrown in the pot, I've probably tried it over the last 15 years. My personal preference is that I smelt with sawdust, and cast very clean ingots. However, when dealing with a casting pot, I use good old fashioned beeswax.
Now, I don't want to get into a debate about whether or not beeswax is a flux or not. My opinion is that my fluxing is taken care of at the smelting level. When I am at the casting bench, I do not care to have little black flakes of charcoal migrating down the walls of my pot and through the spout, and into my mold. This has happenes no matter how careful I am to prevent it. At this point, my thinking is that if I don't want little black flakes of charcoal getting into my mold, then I should quit piling that same substance 1" deep on top of the melt.

Meanwhile beeswax has a very interesting way of reducing the surface tension of the alloy and it flows into the mold more consistently with beeswax present. This goes for the bottom pour pot as well. Ladle casting is especially appreciative of this age old trick. When using sawdust, the stuff is constantly sticking to the spout of the ladle, and the sides, and I ended up banging the ladle on the edge of the pot to clear all the dust that clings to it like greased cellophane.
In contrast, when a small piece of beeswax is added to the melt, and stirred in with the ladle itself, the ladle comes up out of the melt smoking and clean as a whistle, and the silver stream runs out of the spout like mercury. More importantly, the bullets come out of the mold more consistent in weight and appearance, and that is what I am after.
Bees wax in a BP pot works equally well, although if your pot is dry, it takes several treatments to really get the effect. The nice thing about beeswax, is that instead of creating dust that migrates down the walls of the pot to the spout, it does just the opposite. It actually encourages it to release its hold and lifts the crud up to the top of the pot and there it floats for you to scrape off and dispose of.

Now it's true that once all the beeswax burns off and finishes outgasing, you no longer have a barrier to the oxygen, and you also have a very clean alloy which encourages oxidization. However, I don't really care about this because
A. I can just add another piece of beeswax, and
B. I'm not going to lose enough elemental constituents in 15 pounds of alloy over a period of 6 hours, to really effect anything.

I have done quite a few XRF tests of alloy that was melted and scraped over long periods of time, and the only way you'll see a measurable reduction of tin or antimony in your pot is if you heat it and scrape it every day for a month without ever replenishing it. After a month of heating, scraping, and beeswaxing, your alloy will have been reduced in tin or antimony by a staggering .2%, although your entire pot level will have been reduced by a noticeable amount. The reason for this is that the tin and antimony that separate out of the mix take lead with them too. In fact, I XRF tested the silver sludge that floats on top of the melt, as well as the dross scrapings, and while it was indeed high in tin and antimony, it was even higher in lead. Actually it was surprisingly close to the alloy in the pot it came from.

All of this tells me that when smelting, it is important to use sawdust because you are throwing several alloys together and you need them to blend perfectly. Sawdust is the best thing for this (although I throw beeswax in there with it) but once I am sure the alloy is blended well and it's time to cast bullets, the age old adage: cleanliness is next to godliness, seems to apply for me, and beeswax produces better bullets.

All things considered, I have chased this goat all over Knob Hill and found it back in it's pen. Dad told me to flux with sawdust when smelting, and use beeswax in my pot as a casting aid when I was a mere lad of 14 years old, and I believe him to be 100% correct.

The path to precision, accuracy and consistency of the two is as follows and never changes:
Dismiss your preconceived ideas and biases (and everyone else's too while you're at it).
Observe, measure, test, conclude, institute a change (one at a time), and repeat.
Never ignore a facet of data that is available to you.

Never disregard what the data tells you because someone else told you it doesn't matter (this happens in every area of my life. Most of the time I end up reinventing the wheel, but I have a thorough understanding when I'm done, and I can tell someone else why I do what I do.)

This is just good general advice and it has carried me to the truth through all areas of my life from marriage to child rearing, to gunsmithing, to bullet casting, and I dare say, the results speak for themselves.
When it comes right down to it, it either works for me or it doesn't. I am not willing to say something doesn't work without giving it a good honest effort, but when it fails to impress, I drop it and move on.
Using this process, I have learned how to cast excellent bullets that are superb in appearance, and consistent in weight to the tune of +-.1 grains by weight, and I can do it with all the alloys in my shop. This thread is simply a tutorial of how I have accomplished that.
I have posted pictures of the bell curves to attempt to back up what I am saying as the truth as it pertains to my situation, and I am trying to be as transparent as possible about the tools I use to accomplish this feat.
It is my opinion, and mine alone, but I think it's possible others might be able to achieve the same level of proficiency in a shorter period of time, and if so, I am willing to help.
This tutorial is also what I give to people that come to the shop to learn how to cast, and I encourage them to use these tools of exploration to find their own path to success. No one will fail if they remain true to themselves and keep their eyes open as they explore the art of casting excellent lead bullets, and I think I am even more excited to see their success, than they are.

Thank you.

[rking22]

Very informative (and well written) thread, Thank You Tim. Question , I ladle pour and use a 10 pound melt, roughly how much beeswax would you use each time you add it while casting? I used to use wax but had changed to sawdust lust like when making ingots. Noticed just what you described in the last post. So , english pea size ball or more or ?? Again thanks

[MBTcustom]

I use a flat head screwdriver to break off a piece about this size.
132011
Throw it in the melt and stir quite a bit to get the walls of the pot all coated and to help bring the crud to the surface. You'll be surprised how much trash you get.
Just my 2 cents worth.

[SwedeNelson]

Tim

Next time try to stir your bee's wax in with a 3/4" round oak dowel about 10" long or so
Works a lot like saw dust to flux with but not all the ash.
"My father recommended it to me back in the early 80s as well"

Bullet maker, maker
Swede Nelson

[MBTcustom]

Tim

Next time try to stir your bee's wax in with a 3/4" round oak dowel about 10" long or so
Works a lot like saw dust to flux with but not all the ash.
"My father recommended it to me back in the early 80s as well"

Bullet maker, maker
Swede Nelson

Well if the advice came from the guy who raised the best moldmaker in the USA, I guess I had better try it!
Good to see you Al.

[prs]

About char making its way to the bottom of the pot from the surface, I have not had that happen so far as I have realized. I have had that problem when using pine spatula to scrape the pot and quickly went back to using a steel spat. I have quite a nice supply of beeswax and use it in the pot. I do not think the wax really gets into the alloy, I have to roil-up the alloy from the depth of the pot to expose it to the wax up on the surface; the wax is just too volatile and light to submerge.

Again, Goodsteel, great info, and now, Swede has ne ready to slice off a spatula of red oak.

prs

[MBTcustom]

About char making its way to the bottom of the pot from the surface, I have not had that happen so far as I have realized. I have had that problem when using pine spatula to scrape the pot and quickly went back to using a steel spat. I have quite a nice supply of beeswax and use it in the pot. I do not think the wax really gets into the alloy, I have to roil-up the alloy from the depth of the pot to expose it to the wax up on the surface; the wax is just too volatile and light to submerge.

Again, Goodsteel, great info, and now, Swede has ne ready to slice off a spatula of red oak.

prs

Good information prs. Thanks for weighing in (pun intended).
You are very right, the wax cannot get into the melt. It rides on the surface and between the lead and the wall of the pot, and when it outgases it brings the garbage to the surface.
Out of curiosity, would you mind if I ask what pot you are using? It has crossed my mind several times that this might be a problem that is specific to the Lee pots. I would appreciate any additional information.
I am hoping to invest in a RCBS lead pot this year but until then, I cannot make a comparison. This thread is just an explanation of how I have gotten consistency with the equipment I have available.

Thank you.

[prs]

My pots are bottom pour Lee 20#, one came with the new style adjuster screw and another I have adapted with that. Another I picked-up and is on a shelf. I use a PID on the pot from which I cast and I have the other pot running a little hot to receive the spru and "pre-keepers" or "FLBs" (Funny Look'n Boolits). When the casting pot gets low I ladle lead from the reserve pot and then let new ingots melt in the reserve. My PID is set at 730F and I see that is in your sweet range. Iron molds, I run with PID at 700F as they are less cavities and hold heat longer. I rarely ladle cast and mostly use multi cavity molds. I have Swedes 68 clone with pins in aluminum and it is a favorite for sure. No problem with black specks when ingots are clean and no pine spatula.

I
When doing yearly inspections, and inspections before a long trip, removing the radiator cap and checking the coolant level at the cap when the engine is cold should always be part of your inspection. (If Honda was serious about owners doing regular bike inspections, they would have, and should have have found a way to make the radiator cap much more accessible.)[/QUOTE]

Greg (and LarryM)
Sorry if I came off like...a dipstick.
I can see the value of pressure testing. If the cap fails closed the resultant over-pressure could damage the cooling system, maybe blow a hard-to-get-to hose or even break a radiator. If it fails open it may boil under hot conditions and expel coolant and I will probably see that it is puking.
But to number 2., I think he probably had a bad thermostat. Anyway, my point is I think the dipstick (the one in the bike) can be a good indicator of coolant loss, a leak, and was intended to do just that.
So, let's say I'm your average dipstick Goldwing owner (my wife would rate me a below average dipstick) and at my last coolant change interval, like a good boy, I had my system pressure tested and it tested OK and I filled it. I ride around for a few months and check the dipstick and it indicates abnormally low coolant, like none if I really have a leak (more than just evaporation from the bottle). I have not seen any indication of leaking. I add coolant. I ride around for awhile and check the dipstick and it indicates low again. Whala, I'm sure I'm losing coolant so I suspect I may have a leak on the pressurized side of the system. Now I check the cap and do a pressure test.
The dipstick did its job for me. I use it regularly, only for its intended purpose of course.;) have in past done bell curves with boolits. I tended to get skewed curves with the central tendency at the heavy or correct weight and the long tail toward light samples. Makes sense to not have overly heavy samples unless the mold block faces get splattered (oops) or the sprue cutter gets loose to allow bases to protrude (the latter a peculiarity of Lyman molds when the little lead shot under the Allen screws begin to melt - and I replace with snips of copper wire).

Carry on!

prs

[MBTcustom]

Wow, that's an excellent system prs.
I confess, I've been thinking of using my Lee 20 as an alloy prep when I get the RCBS. Now that I see your recommendation of doing just that, I think I will!

For the record, regarding the bell curves, I saw a very interesting trend while I was creating them. If the base of the Christmas tree swung towards the heavy side, then the alloy temperature was too hot. If it swung towards the light side, the alloy temperature was too cool.
When the curve is perfectly centered on the long peak, the alloy temperature is right where it needs to be for optimum consistency.

Also, something I noticed that is very telling. No matter what the temperature of the alloy or the mold, no matter how jacked up my casting process was, no matter how much my bell "curve" looked more like a worn out hair brush, one thing remained constant through all the tests: The longest line of bullets was always the same weight.
As I dialed in my process, that long line got longer and longer till it was just a single string of bullets, but the curious thing was that the weight of the bullets in that longest line never changed more than .1 grains. It was very obvious that the mold wanted to cast bullets of that exact weight, and there was something (actually quite a few somethings) I was doing that prevented all the bullets from coming out that exact weight.
In fact, the only thing I could do to change that constant was to switch alloys. As long as the alloy was the same, that mold was going to try to throw bullets in that long line, and it was up to me to figure out what I was doing to prevent it.
That was one fascinating discovery.

[runfiverun]

paint stir sticks are over 10" long and shaped nicely for scraping the sides and bottom of a casting pot.
ohh they also hand them out for free at the hardware store and the lowes...

[Hannibal]

I have tried paint stir sticks, with less than stellar results. Matter of fact, it was the closest I have come to a visit from the tinsel fairy. If it works for you, then you certainly have found an economical solution. It doesn't get much cheaper than free, after all. But I am going to have to stick with stirring paint with paint stir sticks and bees wax in the casting pot. Just my $.02.

[Sticky]

Tim,

Thank you very much for sharing and illustrating the techniques that lead to consistency. I feel as a new to casting loader, that this is invaluable information and will be a key part of my process as I learn the tricks to produce consistent lead projectiles.

I do much as you, after much research (and a little practice), using sawdust for fluxing when converting wheel weights into ingots, then switching to beeswax for the Lee bottom pour pot. I tried the sawdust routine in the casting pot, but switched to beeswax and I won't look back! The difference is noticeable and I think the beeswax is much better suited to reducing the casting alloy and maintaining a consistent alloy without loosing the key ingredients.

I will utilize your weight sorting and curve to see how my consistency is gaining over time. Thanks again for sharing your research with us! :hatsofftoyou:

[1Shirt]

A super thread! Should be a sticky!
1Shirt!

[MBTcustom]

A super thread! Should be a sticky!
1Shirt!
Thank you very much 1Shirt. That means a lot coming from a member with your experience level.

If applied, this method of self training can make an inexperienced caster progress very quickly to a point of achieving impressive proficiency. From that point, the caster can observe, measure, test, and adjust his/her method to achieve any result they wish. No matter what each caster's personal requirement for their bullets might be, we all share three common goals: accuracy, repeatability, and consistency.
The reason why I encourage each caster to provide themselves with evidence, and proof of the consistency they are capable of, is because if progress is desired, you must be progressing from one point to another. Without some method of monitoring progress accurately, no discerning person could be sure they have actually progressed.

Concerning shooting and loads, we have targets that will give us pretty accurate feedback as to our progress if large enough sample sizes are taken and measured in MOA with consistency being the ability to reproduce those results over a range of shooting sessions and yardages, but I have found the casting pot to bring just too many variables into the equation to make a determination using a target in conjunction with the previous two objectives. I wanted a way to "shoot a target" with my lead pot on the bench, without the detrimental influences of errors with the rifle or the loads.

Now I can depend on the accuracy of the bullets cast and proved at the bench, and the range can be used to tack down load data and issues with the rifle, along with personal skill and riflemanship.

[Sticky]

Okay, decided to apply your sorting method to a cast from the other day when it broke the 30F mark here and I could handle the garage. Ran some 98/2 COWW in my new Noe 30 Hunter mold (188gr).

First run was terrible, they all went straight back to the pot, so I regrouped, upped my Lee pot temp and went at it again... much better results.. this seemed to need more heat in the alloy, also upped my hot plate temp a little to get the mold hotter to begin with. Saved most all of these casts, less about 10% that got sorted at the bench when they cooled (the early casts, etc.. (obvious wrinkled or not filled out)) and remelted.

I took about 100 of them (cast about 190 total after rough sorting) and DTPC'd them and added gas checks/sized.

These are the other leftover saves that didn't get touched yet..


http://i166.photobucket.com/albums/u107/IGluIt4U/bang/016252ca216f53b41b9c61f5aa3c24ae75f3c0661d%20800x6 00_zpskjklepza.jpg

Decided to do the same for the finished boolits, expecting more variance, as they are DTPC'd, which is not as consistent a coat weight, and as was expected...

http://i166.photobucket.com/albums/u107/IGluIt4U/bang/013e93f9da8fb598756e72d23c4deb5923220cc442%20800x3 54_zpsaosjzvom.jpg

Now a couple of comments, as I see that I clearly have some inconsistencies to overcome yet with my process. I did notice when starting to cast with the new Noe mold, that along the way the sprue plate was pretty loose.. too loose. So I took a break and adjusted the sprue plate to get it back right again and resumed. I think this explains some of the variance in the cast weight spreads (the heavier cluster of weights).

I also had at one point, the sprue literally wanting to fall off the mold when I turned it over after the sprue frosted, causing some lights due to the slight removal of sprue from the base of the boolits when that happened. I adjusted my technique a little to eliminate that.

I also ran into issues with seating the gas checks and shaving a little lead from the base on occasion, I suspect as a result of my DTPC, which adds a bit more to the boolit base diameter. I am going to run a batch with Hi-Tek coating and see how they work in comparison. I would prefer to coat these over lube (though a tumble lube is within my capabilities), as I don't have a 'lube die' and don't really want to go down that road at this point in my early start and... they will be running in a 308 AR, so I want some coating to protect them and prefer to not have lube gumming up the works in the rifle over time (but that could be misconception too).

I also have not been 'priming' the pot before starting my cast, which I am sure has some significant effects, especially in the freezing cold weather we are enduring and in my unheated garage, so next time around, I will add that step into the process and see if it helps my consistency as it seemed to help the OP.

Still learning... and experimenting... and smiling all along the way... :bigsmyl2:

[MBTcustom]

Judging by your bell curve above, I see two things going on. First, I would suggest (assuming the exact same casting conditions) you try running your pot 25 degrees cooler.
Second, it looks like you're mold temperature was pretty erratic?
Third, your loose sprue plate was definitely giving you grief.

However, remember the most important rule of casting and shooting: Change only one thing at a time!
You have too much going wrong to really tack down what the problem is, but you can also take your pick from the very likely culprits. Just pick one, control it, and observe the difference.
Any time you run across something that has a wide range in which control may be exercised, you can rest assured that there is a sweet spot in there, so the first objective is to gain control, but then you experiment with that control to find the best place to put it (as I was saying about alloy temperature and timing).

BTW, Awesome PC job on those bullets! They look awesome. I have not seen that color used yet.
You bring a whole different facet to the table with your PCed bullets. I wonder if it would be possible to duplicate the bell curve after PC? Very intriguing.

[Sticky]

Judging by your bell curve above, I see two things going on. First, I would suggest (assuming the exact same casting conditions) you try running your pot 25 degrees cooler.
Second, it looks like you're mold temperature was pretty erratic?
Third, your loose sprue plate was definitely giving you grief.

However, remember the most important rule of casting and shooting: Change only one thing at a time!
You have too much going wrong to really tack down what the problem is, but you can also take your pick from the very likely culprits. Just pick one, control it, and observe the difference.
Any time you run across something that has a wide range in which control may be exercised, you can rest assured that there is a sweet spot in there, so the first objective is to gain control, but then you experiment with that control to find the best place to put it (as I was saying about alloy temperature and timing).

BTW, Awesome PC job on those bullets! They look awesome. I have not seen that color used yet.
You bring a whole different facet to the table with your PCed bullets. I wonder if it would be possible to duplicate the bell curve after PC? Very intriguing.

Thanks Tim for your feedback. I agree, there are a few issues that I need to master yet, primarily cadence and learning the proper temps for each mold/boolit design for the mold and alloy. My first batch was on the cool side, both alloy and mold (I think) as I was getting wrinkles and incomplete fillout.

Correcting the sprue plate made a difference and I know that was hurting me in the early stages of casting with this new mold as the plate loosened up.

I will try dropping my alloy temp a bit. My first batch was obviously too cool and I upped the alloy to 750, perhaps a bit high, but my fillout was good, so I went with it. I was getting a little frosty, but my fillout was good, the sprue frosting time seemed good, so that's what I went with on that batch. I also think that priming the spout will help in these cold Mid-Atlantic temps we have been enduring of late, so the spout cooling (along with refining my cadence) was definitely an issue.

I understand tacking one variable at a time, I have been a troubleshooter for most of my adult life.. ;)

I am not yet using a pyrometer on my mold, but that would be easy enough to do, just need to drill a hole. I will look into that this week. I do use a hot plate to preheat the mold, but understand that rhythm in casting is equally important and I need to refine that a bit as well.

The DTPC is probably not going to exactly duplicate the bell curve, as compared to ESPC (which I don't do.. yet.. lol), but with the Hi-Tek, I may be very close. I will try that and post the results next batch around. That was Smoke's Orange Brown on those and this is Hi-Tek's Red Copper on the batch that was uncoated this morning...

http://i166.photobucket.com/albums/u107/IGluIt4U/bang/01274d1ef6d9f3ed845fe6934285141ef579921998%20800x6 14_zpso8slpltd.jpg

[MBTcustom]

Thanks for the input popper. What you describe is exactly how I used to cast.

Unfortunately, for me, visual inspection is no longer sufficient to achieve my goals. My bullets were consistent in appearance, but closer inspection with the basic tools available to me showed a different story.
I decided that I wanted my bullets to measure exactly the same, weigh exactly the same, and look exactly the same. Judging by the groups I believe the effort at the bench is paying off for me.
Although I must confess I would prefer to cast bullets that are as perfect as I can cast as it pertains to the above criteria regardless of whether it made a huge difference on target or not. I may not be to the point as a marksman that I can detect subtle differences in bullets weight and diameter, or I may not be shooting at distances that it would make a difference, but I would prefer to be ready when that time comes, with good casting habits and proven processes.

[MBTcustom]

Bravo. That is how it's done, and it does not matter what alloy you use. Each one will have a sweet spot.

Just a little back story for the readers; sgt.mike and I worked on this together December 2013 and continued to work on it throughout 2014 to the present. We have plotted dozens of bell curves with all the alloys we have that are usable for casting a bullet out of. The results between the two of us were very consistent in that we always saw a sweet spot in alloy temperature. Also, we both improved greatly in our casting proficiency over 2014.
When we started this exercise late in 2013, my bell curves looked pretty much like sgt.mike's posted above. Where I am at now is clearly shown in the OP.

You too can enjoy this level of precision and consistency with the molds you own. It's exciting and rewarding to see where you are at, and to make a change and observe the result as sgt.mike was good enough to demonstrate.
Remember, it's not about the bullets. It's about the guy holding the mold, and this process will help you refine your process into a fine art.

My father once told me something that has always stuck with me and I believe it to be so: "There is no such thing as magic. Magic is just good science, badly explained".
This is simply using the power of observation to produce a repeatable technique.

Thanks for posting sgt.mike.

[Sticky]

Excellent demonstration sgt.mike! Thank you!

I will work on temps in a similar manner next time I can bear the garage cold for a while (very soon, i'm itchin..lol). I also need to get a hole in my molds so that I can monitor mold temp as well, I think that will be an enlightening facet of the process for me, as a new caster. I need to get a handle on these areas to increase my consistency. Thanks again for sharing! :cheers:

[MBTcustom]

Excellent demonstration sgt.mike! Thank you!

I will work on temps in a similar manner next time I can bear the garage cold for a while (very soon, i'm itchin..lol). I also need to get a hole in my molds so that I can monitor mold temp as well, I think that will be an enlightening facet of the process for me, as a new caster. I need to get a handle on these areas to increase my consistency. Thanks again for sharing! :cheers:

When you get the thermometer in there and start using it, just use it to see general trends at first. I made the mistake of thinking it could be used to replace the timer, which it cant. You have to plug it in and just keep an eye on it occasionally, and you'll start seeing a correlation between what it says, and what you are doing. I outlined the biggest benefits I have found in post #53, but I haven't been using this tool for very long.

Also, I work in an un-insulated garage as well. Just for the record, if you invest in a kerosene heater, it will absolutely run you out of there. Mine was an absolute life saver and much cheaper than the sunflower propane heater I was using in previous years.

[Sticky]

Well, I live in the subfreezing zone this winter and my kero heater has been dedicated to supplementing the fireplace to keep the heat pump from wearing itself out this winter on those days when just a fireplace can't do it, so the cotton duck coveralls serve two important purposes for me in the garage - make it just bearable and protect me from the hazards of molten lead! I know the cold environment is not working for me, but honestly, most of my casting will likely be done in the cooler months and that gives me more time to dedicate to range time in the warmer months. It's just too darned cold to enjoy range time when your bare trigger finger is getting numb from the cold (well, it is for me anyway). So I need to get a process that will allow me to cast in these cold temps with consistency, knowing that I can adjust that, if needed, as the temps rise and I find myself short on a boolit in the middle of the summer and need to fire up the pot again.

I understand your point. One of my early goals in this learning curve is to identify and try to quantify those more critical parameters that affect the consistency of the process and the quality of the finished product and both alloy temp and mold temp are two obvious parameters that fit that bill. I know I can use the dial on the Lee pot and the temp scale on the hot plate that I have, but having hard accurate numbers takes that one step further. I PID'd my Lee pot before I even turned it on, so I can have an accurate monitor for that part of the process and I want to be able to monitor my mold temp as well. I have a meter that will allow me to use a non-contact IR pyrometer, but I have learned over years of measuring temps, that this is not the best way. It is always more accurate and repeatable to use a probe in the metal (IN the metal, not against the outside of it) to monitor the temp of a metal object. Heck, even a small thermometer can be used for this if the fit to the hole is close enough.

The mold is preheated on a hot plate, but I haven't yet checked the mold temps to see if it is even getting to the temp that is indicated on the hot plate, nor even verified the actual temp of the hot plate vs indicated by the dial scale temp. I need to do this to give me accurate monitor of that parameter. For now, I have just been using the tried and proven visual monitors that guide you to that sweet spot (even though I really don't yet know what that sweet spot is.. lol)

I am going to drill a probe location and use my wire bead probe that allows free movement and manipulation of the mold, or at least the ability to spot check the temp by just inserting the probe for a few secs to find out. I have seen the signs of improper mold temps, from poor fillout and wrinkling, to frosties and smeared sprue cuts and have learned to 'time' the sprue frost to try and find a consistent cadence. I know it's much about the timing and less about the other details, but having more hard data to monitor and record will surely benefit the process and my learning.

[MBTcustom]

Sticky, remember what I said about hot plate temperature. Its better to err on the side of too hot than not hot enough.
Your casting conditions are going to make consistency very hard.
First, your spout will need extra priming in order to heat up (you might have to go 1.5 seconds).
Second, your mold is going to be cooling off so fast, you're really going to have to be johnny on the spot with your dwell time (if you dwell at all).
Third, any error in cadence will require you to return the mold to the hotplate immediately till you bring it back up above your maintenance temperature.

The good news is that once you get this dialed in perfectly, you should be able to cast faster than any of us. I wish I could experience what that's like for an afternoon. That would be a very interesting challenge!

Please keep us posted on your progress!

[MBTcustom]

Made a big difference in my reject rate. Did you mic some of the various weights to see if dia. variance was a big contributing factor to the weight difference? I understand Tim's reasoning, to minimize voids in the boolit, just don't think he will find them by weight segregation. I think they are related to what I call 'smily faces' on the boolits. Small 1/10" dia. wrinkles that I believe are caused by contaminate in the melt (or mould), I haven't found any particles but it apparently is a local freezing area. This is my suspected problem with eutectic alloys, not just Lino. They freeze in a very small temp band so there can be no 'migration' of air/junk.

popper, I know exactly what you mean about the smiley faces in the bullets. It concerned me too until I realized that the cause of that is that Linotype has the tin and antimony in perfect solution with eachother which renders a highly reflective surface. When I hold the bullet in front of my face and inspect for defects, I can clearly see a smiling face in the surface of the bullet.
This is nothing to be concerned about, and I personally believe it has no bearing on the accuracy of the bullets on target, but like the rest of what I have written in this thread, that is my opinion only, and I hold noone else to it.

[Doc Highwall]

Tim and Mike, what distance approximately is the sprue plate from the bottom pour spout that you are using?

[MBTcustom]

Tim and Mike, what distance approximately is the sprue plate from the bottom pour spout that you are using?
About 1/4", or as close as I can get it without dragging the puddle.

[MBTcustom]

On that note, I did experiment with different spout heights and I have never found a long throw to give consistency, and in fact, increases the chances of air bubbles being trapped in the bullets.
I keep the spout height at about 1/4" mainly because if it were any closer, I couldn't aim the stream any longer, and I find that giving up a little in the spout clearance area, to gain the ability to attempt consistency with aiming the stream, to be a very reasonable trade-off.

This issue is another that can be settled with the bell curves, and I confess I never really experimented with it, but I encourage anyone else to do so if you are so inclined.
As with all the rest of this: exercise control at several different levels. If there is a difference, then pick the best one. If there is no difference, then don't worry about it anymore.

What has surprised me up till now is how things that I really thought shouldn't make a difference actually do have a significant impact on consistency. In fact, I have yet to find a single thing that does not effect the bell curve somehow. In each facet of bullet casting, I have found there is a right way and a wrong way for me to attain consistency such as I describe.

[MBTcustom]

So today is casting day and I decided to focus on COWW straight up just to see how close I could get. Mold used was the 30XCB.
COWW is on my list of "good" alloy's but certainly not excellent, and this is why:

I ran the bell curves this morning to find the ideal alloy temperature, and found it at about 705 degrees. Unfortunately fillout was terrible due to the surface tension of this alloy so I bumped up another 10 degrees to try to aid the fill out and experimented with dwell times. I tried a 6, 10, 15, and 20 second dwell times, and settled on 15 seconds as ideal for maintaining a mold temperature of 450 degrees, and a 2.5 second puddle freeze.
I ended up casting 300 bullets like this, but there were many lube grooves with rounded edges, and worm trails etc etc etc. This is just a tough alloy to get good fillout with, and I found myself in a catch 22 where I could bump the temperature up and get better fillout, and blow my bell curve, or I could maintain the ideal temperature (a little on the warm side) and do the best I could.
I went ahead and plotted this bell curve with some of the bullets. I had about a .7 grain variance (terrible IMHO) and the curve clearly shows the alloy was a little bit on the warm side. This is why we add tin to the COWW fellers. Yes, it toughens up the alloy and makes pretty bullets, but the main thing it does is reduce surface tension, which tricks the alloy into thinking it's being used at a much higher temperature, while at the same time actually lowering the ideal operating temperature. Like using a slow twist barrel, it just makes sense to do the obvious thing to make your results consistent.

Again, notice the preference the mold had for erring on the heavy side?
132557
That's telling you that the alloy temperature was too hot. This was one of the most interesting discoveries I made when doing this bell curve project. I always line the bullets up with the light ones at the top of the page and the heavy ones toward the bottom. If the curve error showed a preference towards lighter weight, the base of the christmas tree swings it's hips to that way, and it means the alloy temperature is too cool. If the alloy was too hot, then your christmas tree will swing the bottom towards the heavy side, but the point of the christmas tree will always pinpoint the ideal weight that the mold wants to cast with that alloy.
I think that's pretty neat.
I never read about anybody doing bell curves with their bullets before, and the two points I just made have certainly never been told to me.

[MBTcustom]

Thanks for your input popper.
So what do you recommend our readers do to increase their consistency? so far, what I have gathered is that you do not weight sort, you do not control temperature, you do not control timing, and your inspection process is completely based on visual observation.
I have demonstrated my proficiency such as it is, but I am very interested in improving myself beyond where I am now (as is everyone who comes to this site).
What would you suggest I do?
How can I progress?
How will I know I have progressed with my casting and not just my riflemanship?
How can I gauge my progress?
Please help us learn!
Thank you sir.

[MBTcustom]

Thank you sir, but perhaps we have a differance of opinion when it comes to consistency?
When I say consistency, I mean as measured with the tools I have available to me (that would be my scale, and my micrometer).
You have stated that neither of these tools are worth using in your opinion. That being the case, the only thing left is visual appearance of the bullets. Would you not say that visual appearance is a very subjective metric by which to judge proficiency, and/or to educate the inexperienced with?
If visual appearance is all you use to test your bullets for consistency, how do you know you have improved? Moreover, how can you teach someone else to improve?
And why would you be so adamant about ignoring the basic tools available to every reloader on his forum?
I'm very confused by your aversion to measurement and documentation, and the resultant improvement. What negative effect would these common tools of measurement have on the accuracy of the bullets? I am trying to wrap my mind around your casting philosophy, but it's not coming easily. Could you please expound?

[kbstenberg]

Goodsteel and Sgt.Mike I wish there was some way that I could express my gratatude for opening my mind on how to improve my casting tech.
The last long paragraph in post 91 opened my mind to thought I had never even considered!!!
And Mikes example of how he narrowed down the melt temperature preference. Clarified how to go about my own tests. Thank you so much Kevin

[MBTcustom]

Thank you popper. Honestly, I can't argue with any of that. Certainly as it pertains to pistol bullets (low speed at close range) or rifle bullets at less than 2000fps/120,000rpm at 100 yards.
No argument from me. However, I personally believe that at velocities of 2700fps+, at ranges of 200yds+, and with a group size goal of 1moa or less, and RPM approaching 140,000 these things do in fact make a difference.
I would be shocked if creedmoor handgun competitors do not care about the absolute consistency of their bullets and find a direct correlation between consistent projectiles, and consistent scores.

That said, I have stated repeatedly in this thread that I am not doing this to sort my bullets by weight. That is absolutely not why I posted this. For 99.9% of the shooters on this forum the weight of the bullets means very little, and sorting them by weight is an absolute waste of time (although, the harder you push them, and the more you expect of them, the more stringent you are likely to get about the quality of the actual bullets themselves).
However!!!!!!
I am advocating that a shooter can sort out his casting process by plotting bell curves based on the weight of the bullets. By using the bell curves to whip their process into submission, it is possible to reduce his/her cull rate to practically nothing.

Rather than hold people to a set regiment of casting that may or may not work for them depending on their equipment and it's similarity to the average, I am explaining a way by which each caster can teach themselves what works and what does not. This is not a way to trap someone into one way of doing something, this is simply teaching people how to observe their consistency with a scale, rather than a firearm (after all, a scale is a much less expensive way to measure than burning two pounds of gunpowder) and to see immediately what effect changes have when/if they make them.
Once a caster has matched their process "prescription" to their unique skills/equipment, they can learn to realize their best potential, and think for themselves, rather than blindly following a certain process. A caster who utilizes this method will do things in a certain manner, will understand why they do so, and will be able to explain why they do so, on demand, as I have done here.

I am a fan of self sufficiency, personal education, and self reliance. This method provides all three.

[boltaction308]

Goodsteel and popper

I have not had a chance to read everything on this thread but what have read has been very informative and eye opening, thanks and keep up the good work

[MBTcustom]

Goodsteel - I think if you are looking to find voids in boolits that would cause 'bad' boolits you might look into the devices used to check welds, paint thickness, etc. They work like sonar (TDA) to measure density. Might try a local body shop to test? Or oil field welders?

Thank you for the suggestion popper, but like I have stated many times, even though this process will find voids, the object is to never have them in the first place, which is why I am advocating using this process for testing the person running the mold, rather than the individual bullets that person is producing.
Culling bullets by appearance, weight, diameter etc etc etc, is only killing the ants. By directing this process at the person running the mold, you are sorting out the problems at the source. After all, the mold does not change from one drop to the next. The alloy doesn't change. The temperature of the alloy doesn't change. If you are experiencing voids, wild variations in weight, variations in diameter, or lousy looking bullets, it's not the fault of the mold or the pot, it's the caster that made the difference. No amount of shooting will change that, and no amount of casting will improve the results unless the caster finds a way to focus on his part in all this first and foremost.
This method shows voids, wrinkles, size and length variations, base fill out problems, rounded lube grooves, and just basic bad timing on the part of the bullet caster, but it doesn't really focus on any of them specifically unless the caster chooses to use it in that way. What this method does do, is demonstrate the overall casting consistency of the person running the mold, and shows improvement or lack thereof.
At the end of the day, there is no way that you can cast +-.1 grain strings of 100 bullets without you having done many things very very right.
In this way, the bell curve method is a catchall and will help a caster solve any problem he/she might be dealing with.
It is possible to tack down any one of the various ways of measuring bullets without capturing the others (you can have perfect bases but wrinkled bullets, good diameter with voids, good diameter consistency with weight variations etc etc etc.) but the only way they will all weigh exactly the same is if all these things are nailed down together.

So why is it that I call some of these things errors? What do I use as a way to judge what is right, and what is wrong?
Its actually very simple: Any characteristic that cannot be accurately reproduced in each and every bullet is an error. If it's not the same every time, then it will have an effect on group size at some point. Take that to the bank.

But it's the very nature of these "errors" that makes them able to be detected by this learning tool. The fact is, they are wrong because they are never the same, and the fact they are never the same is exactly why they will be caught by the bell curve, just as they will be caught by group size eventually. In other words, the only errors that this method does not catch (speaking of the caster or the bullets themselves if you insist on looking at it that way) are the ones that are always the same and very consistent. Of course, that begs the question: If an error is 100% repeatable, reproducible, and consistent, is it an error at all? I don't think so.

[Doc Highwall]

Tim, I think of consistency applied as prevention is better then cure.

This reminds me of someone who buys one of the fixtures that measures and straightens your loaded rounds by bending the loaded round, instead of figuring out what in their seating die set up is causing the run out in the first place and fixing it.

[MBTcustom]

Tim, I think of consistency applied as prevention is better then cure.

This reminds me of someone who buys one of the fixtures that measures and straightens your loaded rounds by bending the loaded round, instead of figuring out what in their seating die set up is causing the run out in the first place and fixing it.

Thank you sir. That is a great way to put it, and is exactly what I am saying.

I started the previous thread because there were several people who I noticed were plotting a bell curve for each and every casting session, and were just using it to find defects and cull them. I was trying to tell them that they might be focusing in the wrong place. Once the sweet spot is learned and written down, you are able to cast excellent bullets, and only the occasional check is required to keep yourself at optimum consistency.

Everyone I have told this method to, immediately either supports or condemns it as another way to cull "bad" bullets which is not what I was advocating at any time.
I have unsuccessfully tried to explain, that even though you can use this method to cull bullets, that is not it's real strength. The real strength of this method lies in finding where each mold likes to run, and more importantly, teaching yourself how to be consistent.
That's why I called the thread "Consistency applied" rather than "Cull for consistency" (which is in fact a contradictory concept).
The object here is to work yourself out of a job!

I hope that the readers can realize the purpose, and potential of this method as I have. It has taken me to levels of consistency that I never thought possible, and like I said in the OP, now I can take my pot off the shelf, add the alloy I prefer, heat everything up and just start casting good ones (like, REALLY good ones) right away.
I would like everyone to be able to enjoy casting like this.

[Jevyod]

All good info here Tim. One thing that I found out I was doing wrong was casting way to fast. I would only wait till the sprue froze, then cut and refill immediately. I just got back from casting 130 420 grainers for my 45-70. I slowed down my pour until I was doing one every 45 seconds. I had the melt at 750. With that temp, I am getting just slight frosting. I looked at them, and they look better than they usually do. I haven't taken the time yet to weigh, but plan to do that within the next few days. I actually enjoyed casting this way more than normal! I used to be afraid that any little pause would cool my mold too much.
So I am learning and trying to apply all I learn! I actually just ordered a hot plate for my mold so I can keep that more consistent. Next comes a pid (hopefully!!)

[Doc Highwall]

Tim, you could also say that it is better to be proactive then reactive in achieving consistency.

[MBTcustom]

Tim, you could also say that it is better to be proactive then reactive in achieving consistency.

I could also say, you have an absolute propensity for condensing 1000 of my words into two lines.
LOL!
Thank you sir!

[Jevyod]

Well I keep learning! Now that I am actually paying more attention to what is going on, I see I need to change. I started weighing my bullets tonight, and was seeing weights from 408-410. Then I noticed that where the sprue was cut, sometimes there were little voids. Am I right that that comes from cutting the sprue too quickly? I looked for some that were not torn as bad, and sure enough, they all were at the top ends of my weight. Now they weren't torn very badly, but it seems like it was enough to vary my weights.

[Doc Highwall]

A dull sprue plate can do that also. When I cut the sprue I apply downward pressure on the sprue plate and twist at the same time.

[MBTcustom]

There are a few things you can do to help that.

1. The trick is to control your temperature exactly and cut right in between the time that the puddle freezes and it changes color. It's nearly impossible to describe this via this post, so take my word that it is in that area. Just start experimenting with it, but be consistent with your experiments. A perfect cut is accomplished the same way everything else is when casting a perfect bullet. It boils down to temperature and timing. Your timing can be spot on, but if your temperature fluctuates, you're going to find yourself chasing rainbows, and the same is true if your temperature is consistent but your timing is off.

2. Use an excellent alloy such as described in the OP.
If you are casting with straight COWW, then add tin to the pot. Assuming you are using a fairly full Lee 20lb pot (15 pounds COWW), depending on the form your tin comes in, add as follows:
40/60 solder, add .85 pounds.
50/50 solder, add .70 pounds.
60/40 solder, add .57 pounds.
63/37 solder, add .55 pounds.
pewter, add .40 pounds.
Pure tin, add .34 pounds.
These figures are based on my experiments with XRF testing of alloys before and after making changes. I find I can pretty much call my shot when smelting if I adjust my alloy calculator to reflect COWW as having no tin at all and 2.3% antimony. It has been very consistent for me when smelting large batches of COWW and having the resultant alloy analyzed for content. I have found no trace of arsenic in my tests, or at least none that amounted to a measurable trace when the alloy was analized. For all intent's an purposes, COWW is 2.3% antimony, and 97.7% lead. Often, there is .1-.3% trash in there that could be almost anything up to and including gold, but whatever that .2% is, it seems to make very little difference batch to batch, so I ignore it. (Again, it is consistent, therefore, it is not an error.)
The tin will help you with fillout, and reduce surface tension, but it also helps you get a clean cut.

3. sharpen your sprue plate holes. You can accomplish this very carefully with a good quality knife, but the best thing is to use a very sharp, 90 degree counter sink. Either way, be sure to use 400 grit or finer sandpaper with a flat backer, or a flat india stone on the underside of the sprue plate to remove burrs and hone the cutting edges razor sharp. Your sprue plate is a scissor, and needs to be sharp. This should never be done to a sprue plate made of aluminum, because sharpening it cuts through the hard anodizing and will allow your sprue plate to dull rapidly and you will be replacing it very soon after.

4. Adjust the keeper bolt (if your mold uses one) so that the sprue plate is held tight against the top of the mold when shut. Don't go crazy here, but what you want is for the sprue plate to swing shut with light pressure until it contacts the keeper bolt oposite the hinge bolt. At that point, I like the sprue plate to be seated in place with a little more pressure. If you can't feel the sprue plate sliding under the keeper bolt, then it's too loose and needs to be tightened. There is a very good reason newer molds have a bolt head there instead of just a stop pin like the old Lymans used. Use it to your advantage to keep that plate evenly captured on both ends with the bases of all your bullets between those two points of contact. This will aid in consistent bases.

5. Like Doc Highwall mentioned, when cutting with a gloved hand, push the plate down on top of the mold, or if cutting by strikeing with a stick (or a small rubber hammer in my case) strike at a slightly downward angle to accomplish the same thing. Remember, your sprue plate is a scissor. When cutting with a loose pair of scissors, you naturally use the handles of the scissors to provide pressure to keep the blades in firm contact with eachother. Cutting a sprue is no different.

[OuchHot!]

The last thing the moderators need is me making work for them BUT; would it be possible to link Goodsteel and Sgt.Mike's posts into one sticky? Not that others have not contributed but their methodology is basically the scientific method applied to casting and it might give newbies a quick start.

[Larry Gibson]

I've shot a lot of Laser Cast bullet and for the most part they are excellent commercial cast bullets. Based on your sampling 35% of those bullets are way outside the acceptable weight variation parameters I've found through considerable testing to be necessary for accuracy at HV. The Laser Cast bullets are certainly just fine for regular 30-30 velocities but when you push them faster the accuracy (group size) will get larger.

"a 0.75" x 0.001" lead sleeve"

What is the 3rd dimension (required to get cu. inch or weight) you used to get the figures you computed?

If you randomly shot 10 shot groups using the 34 Laser Cast bullets from the sample you show the centrifugal force will cause a much larger dispersion in group size with the 1.5 gr variation than if you used 10 bullets from the 22 that weighed the same. Those 10 bullets of the same weight would more than likely shoot a smaller group, all other things being equal, than a random lection of 10 bullet from the 34. Bottom line is; the greater the weight variation the greater the imbalance. The greater the imbalance the greater the group dispersion will be. The higher the velocity, the greater the RPM is and thus the greater the centrifugal force is which is what causes the group dispersion.

Larry Gibson

[MBTcustom]

That's very interesting information about commercial cast bullets popper, and I appreciate you posting it.

However, I still get the sneaky suspicion that you think I'm using this method to prove bullet quality, and I'm supporting a caster using it to check his/her bullets for accuracy, so he/she can keep the "good" and cull the "bad"?
That's not why I wrote this as I have repeated over and over (although, if you expect to shoot in extreme circumstances with your bullets, I think you'll realize a very real advantage to having them all be exactly the same weight, diameter, length, hardness, appearance, and seated with uniformed GCs).

This method can be used to cull bullets if you absolutely think it makes that big of a difference, but the fact of the matter is that if you can measure variances in weight and diameter, then all the variances that you cant measure are going to be much worse than what your scale or micrometer is telling you. If your process has been whipped to the point that you have found a way to reduce the occurrence of errors you can measure, you can be sure that you have also reduced the occurrence of errors that you cannot measure as well because all these things are tied together.

This process is used to reduce the consistency errors in yourself, not the bullets. You are the cause, the bullets are the effect. Observe the effect you can see to correct the cause that you may not see.


Fix the problem at the source, not the effect three steps away.

[Larry Gibson]

"I will restate my original thesis - dimensional differences cause the observable weight difference (plus bad sprue cut) - you can't weigh the bubbles - if they occur. To imply you can is a fallacy."

With 30 caliber cast bullets of 150 - 180 gr from various moulds/designs of any ternary alloy I can easily demonstrate the accuracy difference of a +/- .3 gr difference in weight and can demonstrate it on demand from different rifles ("regular", sporters and target), especially when you push the RPMs over 140,000. Granted at "24000 RPM" the amount of dispersion difference probably isn't all that much if you get the bullet to stabilize at that low of a velocity (334 fps from a 10" twist)? However, at 140,000 RPM (1940 fps (in a 10" twist) the difference will be measureable. The higher the RPM the greater the dispersion will be.

I have, on numerous occasions, taken the bullets that measured .5 or more less than the average and filed on them and found bubbles. Those bullet do not shoot well at all. That is not a "thesis" but is demonstrable at will and thus moves from being a "thesis" to being fact which is not "fallacy".

Larry Gibson

[OuchHot!]

In the bad old days, our molds were not always as perfectly formed as today. I would imagine that a relatively small difference in center of form and center of mass would be quite telling. John Barsness had a bullet spinner built for him that gave some sort of indication of dynamic balance. I wonder if he ever published data on measured out of balance vs rpm vs group dispersion. He is mostly a sptzer j type person but the data might be interesting.

[Larry Gibson]

Bryan Litz (Applied Ballistics For Long-Range Shooting) spells it out as do many other ballisticians as well as many reloading manuals (Sierra, Hornady and Speer). To quote Bryan Litz who puts it in verbiage we can easily understand, from his book on page 144 about a quarter of the way down the page; "Any imperfection in the shape, balance, or alignment of the bullet will cause it to disperse away from the bore line when it exits from the muzzle. The amount of dispersion is related to how severe the imperfections in the bullet are, and also how fast the bullet is spinning......The relationship between spin rate and dispersion is stronger for low quality bullets." Thus bullets with a 1.5 gr weight difference are going to disperse farther apart at a given distance than those with a smaller amount of weight variance all other things being equal. How much dispersion variance is going to depend on the size and location of the imbalance, the rate of spin (RPM) and the distance to the target. This why we also seek linear dispersion tests to see if dispersion is linear and if not the load is exceeding it's RPM Threshold.

Larry Gibson

[MBTcustom]

Just a thought on an internal void. A "bubble" if you will. Like my mentors always say, you have to look at what is not there just as much or even more than what is there.
A small bubble of air is very very light and would not cause much of a difference. However, the bubble sized pocket of lead that is missing actually does remove a significant amount of weight from that location in the bullet.

Concerning weight sorting, I think a thread should be started on that subject, or against that subject, or both. That has very little to do with what I am doing here (as I have mentioned several times).
This is a discussion about proficiency and consistency at the pot by the caster, and a method he/she can use to improve themselves. Just because I'm telling people to line their bullets up in a row based on weight does not mean that I am advocating weight sorting. All I'm suggesting is that the bell curves can be used as a sounding board to find out where you are, and learn how to improve.
That said, as long as the bullets are all lined up nice and pretty, and I'm going to shoot them anyway, I confess I do scrape the weird ones off the bottom of the bell curve and throw them back in the pot.
Yep.
All 11 of them. LOL!

[fast ronnie]

Another excellent post in a long line of excellent posts. Thanks for taking the time to share. I have a question though--- will a really high quality boolit make the rifle quit shaking while I'm trying to aim?

An excellent bullet may not cure the shake while you're aiming, but a badly loaded round could definitely cause a shake after you pull the bang switch.

[MBTcustom]

I was on the phone with a good friend tonight. He said something that cracked me up so bad I almost died. He said and I quote: "Just pour the hot stuff in the square thing!!!!"
[smilie=l:

[MBTcustom]

Bubbles - yes they do exist. Only thing I can think of causing them is moist dust.

Moist dust huh.
I always thought it was something like throwing the alloy into the cavity so fast the air couldn't escape through the provided vent lines.

Regardless, the question is; can voids in the bullets be detected with a scale, and I proved conclusively that they can, along with a lot of other variances, but more like a general "health and well being" of the bullets as a whole. If you can't drop your bullets so that they appear consistent with the basic tools we have available, it's certain that the rifle is going to choke on them too (unless of course, you feed it carefully and limit yourself to low speed, low pressure, low RPM, low accuracy standard, etc etc etc.)

However, regarless of whether you demand perfect bullets, you should at least be demanding a casting proceedure that allows you to do your best, and you should always be looking to improve yourself. It's a fact of being human that if you are not progressing you are sliding backwards. There is no "set and hold" when it comes to skill. You are either getting better or you are getting worse. If you think you are just holding still, I garantee you that you are actually only learning bad habits that will be very hard to break. I say this as someone who has mastered hundreds of skills. I wish I could tell you that once I learn how to do something, I just clip it to my tool belt and it's always there if I need it, but this is not the case. When it comes to personal skill, there are only three options:
Use it
Lose it
or corrupt it.
If you are under the impression that you have a skill that the above options does not apply to, then you are actually in one of the second two and you don't know it yet. Of the two negative options, "Lose it" is the better because you don't have any bad habits, you're just not improving your skills in any way. " Corrupted" skills are the worst, and if you actually use your skill sets to earn a living, you learn to fear this above all else.
This method is a way to keep yourself on the cutting edge of improvement and to keep you on your toes whether you need bullets this precise or not. More importantly, if the day comes that you start getting fliers, ans bad groups, this will be something you can use to check yourself and get back on the horse quickly so that you can get back in the power seat and regain control of yourself.
This is good stuff here. I don't know of any method that is this powerful and simple for staying on the edge of perfection.

[kbstenberg]

I have been applying some of my new knowledge.
All bullets cast with COWW +2%sn, PID temp controlled, Mold temp monitored. All sprues were cut immediately at freeze (there was no more than 1 second of molten lead on sprue), drop bullets, count (designated) seconds, close mold, count (designated) seconds, run a free lead stream, re-fill mold.
These are my bell curves
Pot temp 695 deg. a count of 4 sec. after bullet drop to close the mold, a count of 6 sec. rest before re-fill. Bullet variation was 1.5 gr. I forgot to record mold temp. but it varied only 5 deg. Bullets had miner frosting. No wrinkles or worm tracks.
197.3 gr = 1 bullets
197.5gr = 3
197.7gr=3
197.8gr=11
198.0gr=19
198.1gr=17
198.3gr=13
198.5gr=14
198.6gr=4
198.8gr=2



second casting melt temp 695. A count of 6 sec. until mold was closed and a count of 8 sec. until re-fill, If I didn't hurry to cut the sprue I had to use additional force. Bullet variation was .8gr. Mold temp was about 15 deg. under first test. Bullets had no frost. Good fillout, no wrinkles.
196.1 gr = 1 bullets
196.3gr= 12
196.5gr=24
196.6gr=23
196.8gr=13
196.9gr=7
Tomorrow I will test at higher melt temp. Kevin

[Larry Gibson]

Why it's important and beneficial to me to be consistent in casting and weight sorting.

I've done this sort of test many times before and the results always come out the same; if I want the best and most consistent accuracy, especially at high RPM and high velocity cast consistently bullets of the same weight and dimensions is necessary.

I had some 30 XCBs cast of #2 alloy which was WQ'd. The BHN was 21 - 23. I had weight sorted them and had a batch that were 154.3 gr in weight. I decided to test the 1.5 gr weight variation that has been mention recently. That would be a +/- .75 gr from the 154.3 gr. Sorting through the lighter weight culls for the "-" side I found a 153.4 and a 153.8 in weight that did not have any visual defects. On the "+" side I found a 154.8 and a 155.1 w/o visual defect also. That gave 6 that weighed the same, 2 lighter and 2 heavier with the 1.5 gr variation. I loaded them over a standard load that runs right at 2900 fps out of my 30x60 XCB rifle; Dawn.

I shot the test this morning. There was hardly any wind and the temp was 60 with a 16% humidity. Target was at 100 yards. I had marked each of the lighter and heavier bullets and spread them throughout the 10 shot test string. I tracked each shot on target and the sequence in which fired. The 2 lighter bullets were #6 and #8. The 2 heavier bullets were #3 and #9. As we see the 2 lighter bullets gave the 2 highest velocities and really went out of group giving an overall group size of 3.3". The 2 heavy bullets also were a bit out but still stayed within a 2" group with the main group. The main group of all the same weight bullets (6) went into a tidy group of .85". That's at a muzzle velocity of 2892 fps!

This once again demonstrates the necessity of consistent cast and the need for weight sorting if we want the best accuracy we can get at high velocity or any velocity for that matter. It's why most cast bullet benchresters and target shooters weight sort also. On the other hand I suppose if I was just blastin" with an AR out to only 100 yards the 3.3" accuracy would be sufficient, or at least it is with several milsurp rifles I just use for blastin' or rock shooting.........however, I did not build Dawn to go "blastin" so being consistent in casting and weight sorting is important to me. The proof is in the shooting.

Larry Gibson

133638

[MBTcustom]

I have a couple thoughts on that.
First, RPM is RPM, centrifugal force is centrifugal force, and it will have a certain effect on a projectile over a certain amount of time. Since Larry is getting the bullet to the target faster (nearly 3000 FPS) he will observe less effect (this is pure unadulterated speculative postulation on my part) than the same bullets shot out of a ten twist rifle at 1900 FPS.

Second, most shooters would see those fliers, and write them off as a pulled shot, a called flier, "its just cast and you can't expect better", or what have you.
Most cast bullet shooters are less than critical of their bullets in the first place because they have it set in their minds that cast bullets equal sub standard equipment.

I would humbly submit the possibility that the only thing sub standard about our sport is the processes used to cast, load and shoot the bullets, thus the reason for this thread.

Fix the process, correct the obvious proven issues ("excellent" alloy cast with good process control, slow twist barrels, good repeatable lube, etc etc etc), and hold a higher standard.

[Love Life]

I was on the phone with a good friend tonight. He said something that cracked me up so bad I almost died. He said and I quote: "Just pour the hot stuff in the square thing!!!!"
[smilie=l:

Well, that's how you get started making bullets.

[detox]

I have discovered that consistant pour spout location over sprue plate hole is a must when pouring from bottom pour pots. I may fabricate a tray that will allow exact location of mould everytime a bullet is poured and use one cavity only...especially for precision rifle shooting.

Pouring all five cavities at a time is fine for busting rocks.

[MBTcustom]

What is the payback for us 'average' rock buster shooters other than bragging rights at the range.

Absoluty nothing. Just remember to keep your rocks large and close.
Personally, I use a hammer for such activities.

. Riflemanship and marksmanship to me means cutting small groups in paper and demonstrating it on demand. This allows me to shoot smaller rocks further away if I ever develop a taste for them, or feel they are threatening me in some way.
More importantly, any skill I have must be honed in order to be maintained. I got to a place a long time ago where I was no longer progressing in the casting department. I didn't think there was a way to get better or to progress till I started using these bell curves to see what I could not normally detect. It works very well, and I am still making progress! Every tme I cast, I learn more, find better methods, or refine the methods I already developed. That's what it's all about for me. I want to either get better or quit, and I don't quit.
I'm either pushing for what I want, or I walk away completely for a while till I can come back to it with fresh perspective.
This system keeps it fresh and sharp for me, and while it does find bad bullets, the point is, it helps me never to make them in the first place. I do not focus on how to cover up or cull my failures. I focus on how to make myself more successful.
Of course, the easy path is to lower my standards and refuse to look too close at what I make. That way, I'll always feel awesome about what I do, but that's just not something I am capable of doing.

[Love Life]

I got a whole bunch of milk jugs I can fill up with water for ya!

[Larry Gibson]

Well I'll continue to mention RPM whether some want to hear about it or not. To not understand and thus to ignore (just because you don't want to hear about it) how RPM and centrifugal force affects a bullet in flight is about as sensible as ignoring the effect of gravity or the effect of the wind on the bullet in flight. Just because you don't want to hear about any of them does not negate their existence and the affect they have on a bullet in flight. Oh sure, you can ignore them alright and have lot's of fun "busting rocks" if that's what you want.

In the example I posted above the RPM at 2892 fps in the 16" twist was 130,140. Since centrifugal force is a product of RPM the same centrifugal force occurs from a 10" twist barrel at the same RPM at 1807 fps. Thus the dispersion would be the same had the same bullet/loads been fired in the 10" twist. However, an additional factor arises with the lower velocity; time of flight to the target at 100 yards. The time of flight was considerably less at 2892 fps than at 1807 fps and the group dispersion is what you see. Given the longer time of flight with the 1807 fps 10" twist the centrifugal force would have longer to act upon and cause greater dispersion.

Whether or not weight sorting is at all worth it is simply a matter of choice; if your happy with rock busting, throw dirt on the rock accuracy then all's well and fine. However some of us are seeking a bit better than "rock busting" close range accuracy as such. We find bullet sorting and weight sorting to be quite beneficial especially when shooting at longer ranges. Consistency in casting a goodsteel states is and excellent method of cutting down the number of bullets that get "sorted out" thus increasing our production of the quality of bullet necessary for our accuracy objective. I believe reducing the number of "culls" (however you sort them out) obtained through consistency in casting is the primary objective of this thread(?).

Larry Gibson

[MBTcustom]

Popper, if you don't mind me asking, how long have you been casting bullets?

[bdecker9]

I'm just a country bumpkin, but I thought that the spin on the bullet was to correct for inconsistencies present in all projectiles. Would think more spin would cancel out more. Want to say more but I'm at work and this li'l phone kb is irritating at best

[largom]

This is an extremely interesting thread, especially some of the replies. I have weight sorted my cast boolits from the beginning, a long time ago. Why? Because it is a way to measure the results of something I made. I weigh everything, boolits, cases, powder and my scale check weights.
I make bell curves with my boolits then I inspect the boolits that are out of the center loop. I inspect the boolits to see if I did something wrong when I made them,if so I want to correct ME. This is what Goodsteel is trying to tell us. The bell curve will show the mistakes. It is up to the caster to determine what must be done to correct them.
Is all of this weighing and sorting to +- .1 grain necessary? NO, not for rock blasting or close range hunting. So why do it? My satisfaction is that I want something I made to be the very best. I want mine to be better than those made by the factories. I want mine to be better than yours. Mine has MY name on it. Are mine perfect? No, but I am still learning.

Larry

[MBTcustom]

Popper, I've been casting since 1994, and everything you are saying makes sense, and is things I have tried. There was a time when just getting a clean base was the challenge for me, and I would have laughed at someone showing a bell curve made of bullets.
The thing is, this is all connected. A perfect bell curve is a goal like a tree on a distant hill to keep you heading for perfection in all ways.

This does work. It can be used by an advanced caster to up his game at the casting bench, but it can also be used by someone with limited experience to help them get to advanced casting proficiency at a startling rate of speed.
Take sgt.mike for example. He has been casting only two years, one of which has been spent using this method, and I can barely tell the difference between his bullets and mine on target!!! That's astounding! Two years after I started, I was just trying to keep my bullets from being too frosty. Had I known about this method then, there's no telling where I would be now, 20 years later!
I thought maybe, just maybe there are some people like me on this forum who would like to get on the fast track to casting success, so I demonstrated how to do it.

Now concerning the mold thermometer:
A: it only costs $32 and
B: it's a help, and one more point of feedback (I think we need all the help we can get) but it's not vital to improvement especially at the place you are at.

You have a PID and a hotplate, which is plenty for where you are at now if you want to use those tools to help you progress in your skill. Once you get to where you can drop bullets perfectly filled out with flat bases, even color, and dropping within a weight range of .7 grains, the thermometer can help you fillet off another .5 grains so that you can turn your bell curves into racing stripes.

[Sticky]

This does work. It can be used by an advanced caster to up his game at the casting bench, but it can also be used by someone with limited experience to help them get to advanced casting proficiency at a startling rate of speed.

Once you get to where you can drop bullets perfectly filled out with flat bases, even color, and dropping within a weight range of .7 grains, the thermometer can help you fillet off another .5 grains so that you can turn your bell curves into racing stripes.
This is where I am.. a newb, trying to learn and refine my techniques to produce largely keepers by normal standards. This thread has already helped me narrow my variations somewhat, still implementing new process control steps as I go (a step at a time til I think I have a handle on that step) and hoping to continue to narrow my range of cast weights til I cull very few. Thankfully, it's easy to recycle these bad'ns and move on.. lol

Thanks Tim and all who are contributing. It does help some of us immensely!

[MBTcustom]

OK, cast at 700 culled
142.9 3
.7 10
.6 29
.4 12
.3 7
.1 1

Culled were mostly divit in base drive band, rounded base or both, about 30% total.
Culls at 680 were rounded base, a couple of the divits, ~5% total. Weight spread was larger.

Popper, what alloy are you rolling with?

[MBTcustom]

Aha, Heinz 57.
Brutal.
Do you have any COWW lead and some solder?

[Larry Gibson]

I'm just a country bumpkin, but I thought that the spin on the bullet was to correct for inconsistencies present in all projectiles. Would think more spin would cancel out more. Want to say more but I'm at work and this li'l phone kb is irritating at best

No, the spin of the bullet is to stabilize the bullet in flight so it travels point forward.

Consider 30-06 milsurp M2 with a 150 gr FMJ at 2700 fps in a match rifle with a 10" twist and a very good scope. The bullets travel point forward and leave nice round holes in the target at 100 yards. Yet the group (5 - 10 shots) sizes run 2.5 - 3.5"+. Now pull some of the 150 FMJs and load a much better made (better as in better balanced) 150 gr Sierra MK over the same cases, powder and primers as used in the M2 ammunition. You will probably get less than moa accuracy - 1.5 moa with that better balanced bullet.

The same principal applies to cast bullets.

APPLIEDBALLISTICS FOR LONG-RANGE SHOOTING, 2nd edition by Bryan Litz

Page8; “precision is how tightly the shots are grouped together”.

Page144: “The relationship between stability and precision is probably where thebulk of stability misconceptions exist. Gyroscopic stability can affect precision in two ways. First, if thebullet is not adequately stabilized, it will emerge from the muzzle and flywith some significant amount of yaw until it stabilizes (goes to sleep). This situation is bad for precision and addssignificantly to the bullets drag. Thisproblem can be solved simply by insuring the bullet is fired with sufficientstability by choosing a proper twist rate”.

Page147: “2. Bullets that are properlystabilized will go to sleep quickly,without affecting flight performance (BC). If launched with adequate gyroscopic stability, they will fly with nearzero pitching and yawing motion”

[The above are where measuring the TOF andBC of the bullet in actual tests tells us with what twist is best for aparticular bullet. Affected stability isshown by a slower TOF and smaller BC because the drag is greater on the bulletthat has the greater yaw and pitch or which takes longer to go to sleep.]

“It’salso possible for precision to be compromised if the bullet is spinning fasterthan it has to be for adequate stability. [over stabilized in commonverbiage] When the bullet emerges fromthe muzzle of a rifle, it’s spinning very fast. Any imperfections in the shape,balance, or alignment of the bullet will cause it to disperse away from thebore line when it exits from the muzzle. The amount of dispersion is related tohow severe the imperfections in the bullet are, and how fast the bullet isspinning. Higher spin rates produce moredispersion. The situation can create the illusion that the bullet \’sdispersion is caused by excessivestability, but that’s not the reality. The actual stability level of the bullet isnot what causes the dispersion! Theimperfections in the bullet cause dispersion, and the dispersion is isincreased the faster the bullet is spinning. The more balanced the bullets are,the less dispersion will result from spinning them faster. One of the reasons why short range Benchrestshooters choose to shoot short, blunt, flat based bullets [sounds an awful lotlike a cast bullet] is because they require such a slow twist rate tostabilize. The slower twist barrelsaggravate the imperfections of the bullets much less than faster twist barrels,and smaller groups result.”

Page146 under “Conclusions”: “In general, improved precision can beexpected from slower twist barrels (as long as the twist produces satisfactorySg [gyroscopic stability]) because the slower twist barrels don’t exaggeratethe components of dispersion that are cause by imperfections in the bullet.”

As we see the "spin" of a bullet is what cause the dispersion of bullets.

Larry Gibson

[bdecker9]

Thanks Larry. I've been thinking about that since 415 am. I knew of over stabilization , and thought of this. I've been thinking about drive shafts spinning, and when there's a problem you slow down or speed up and can feel it. And of out of balance tires. Like you go 50 -60 mph and they wobble but above and below that speed is hunky dory, and trying to think of how to relate it to this. And just as I read "point forward" I remembered more of why Greenhill was doing his research in the 1st place.

This is definitely a great thread. I have learned a few simple things that, prior to reading, had me scratching my head.

Sent from a keyboard the size of a 50© coin

[MBTcustom]

Isotope core lead is supposed to be 96/1/3
Hardball alloy is 92/2/6
(that's lead/tin/antimony respectively.)

This quote from Laser cast bullets:

The inclusion of silver in conjunction with our proprietary blend of 7 other virgin elements produces an unbeatable bullet of unprecedented toughness, consistency and precision.

I'm confused. What were you trying to achieve again?
I mean what was your target alloy?

Also, why add copper? It has been proven that standard COWW + 2% tin can be pushed to 2500fps with superb accuracy from a barrel of the correct twist rate.
Seems like a lot of money and work to get an alloy that you cannot reproduce to achieve a goal that is easily met by alloy that can be easily obtained for a fraction of the cost of the firearm you are shooting the bullets out of.

Concerning your copper enhanced alloy, I shelved the idea for the time being because although it makes a very tough bullet, I found shrinkage and mold fill out to be a problem that needs addressing by heat or some other means.
Looks like you're finding out the same thing.

[MBTcustom]

its a good thing you chose a short bullet for this effort.
But back to your 8 element, copper enhanced, silver infused alloy:
You're having issues casting with it.
This meathod as I have described it will help you determine what is working and what isn't.
I suggest you cast 100 bullets, arrange them as described in a bell curve (I would actually recommend you seting them nose down so you can see the bases).
Observe, change one thing and repeat.
Dial in your ideal alloy temperature first, then mess with your timing till you get where you want to be.
Changing two of more things or failing to observe your progress is a recipe for spending a decade learning what you could learn in one afternoon of testing.

Also, not to bust your bubble, but I wouldn't get my hopes up about shooting sub MOA out to 200 yards or further unless you have a very long barrel on your AR. You're at the ragged edge of the RPMTH there at 144,000 RPM, and that short barrel and your gas system is going to make things even more challenging. I'd say you're in for a difficult time getting consistent and dependable linear dispersion from that setup.
However, this further underscores the need for absolute process control at your casting/loading bench, as well as careful note keeping.

[MBTcustom]

Oh, COWW usually has a bunch of stuff besides the Pb,Sb,Sn in it.

As one who has done more XRF testing of COWW alloy than anyone on this forum, I can corroborate your statement, and also add that the total percentage of impurities rarely exceeds .2% (not enough to make much of a difference at all.
The way the alloy responds to heat and quench is also very consistent as long as you smelt in large batches of 100lb or so (I usually go 150lb batches).
Individual COWWs vary in composition somewhat, but taking a pot full of 150lb of them and analizing it has proven to be remarkably predictable: 2.33% antimony, less than .5% tin, and less than .2% whatever that hemisphere of the periodic table contains (for the record, I have yet to find much trace of arsenic at all).
I have found that if I reassign my calculator values for COWW to 2.33% antimony, 0% tin, and 97.67% lead, I can hit my target alloy exactly every time when smelting with other alloys of known content.

Basically: Yes, there are impurities and trace of as many as ten metals in COWW, and it is so minute it doesn't amount to a hill of beans.

However, intentionally spiking the alloy with significant amounts of copper, silver, and who knows what else, is going to have a very real and measurable effect on bullet quality. One of the worst effects that copper contaminated alloy exhibits is bullets that are not straight. This is easily seen by putting the bullets in a precision collet lathe and measuring their TIR.
What I see is bullets that are about as straight as bananas (ie: you're shooting with bent arrows) coupled with bad fill-out, and the bullets come out undersized.
(For what it's worth, I also measure my target bullets in this way cast of "excellent alloys" as described in the OP, and I will always find 2 or three out of 100 that are warped. I do not know what causes this, and the bell curves can not tell me anything about it either. This is one test that I certainly do use to cull bullets with, simply because I have no idea of how to prevent it in the first place)

So if you don't play your cards right, whatever you gain in bullet toughness, you will lose in bullet quality (and then some). This compromise only works if you maximize your bullet quality to the point that you can realize the positive effects of the toughness and give up as little as possible in the consistent accuracy department.
In that regard, I would refer you back to the OP on this thread as it will help you find the best place to run with that alloy where you can realize the best effect. I don't think you're ever going to get racing stripe bell curves with that alloy, but you can definitely find the best process to make your bullets as excellent as possible.

[Love Life]

This thread does a great job of showing both the art & science of bullet casting.

[Larry Gibson]

Most of us these days use an electronic scale to weight sort cast bullets. Electronic scales by necessity have a +/- accuracy range. I have tried several over the past years and have settled on the Hornady GS-1500 for my own use. It comes with a 100g calibration weight and is easy to use. Anytime the scale reads other than 0.00 when the bullet is taken off I recalibrate. That gives me as good as consistency as I've gotten and is better than with any other scale.

Another consideration for "consistency" is just how "consistent" is your electronic scale and that begs the question. I just completed weight sorting 531 linotype 30 XCBs. The GS-1500 has a "resolution" of .1 gr which I've come to realize is close to a .075 gr +/-. Where the acceptable range begins and ends is dependent on the median weight selected. Using a tried and true Redding balance scale which is zeroed and calibrated with certified weights on which I can read to .05 gr I decided to test 20 selected bullets from the batch just weight sorted. I randomly picked 20 out of the batch the GS-1500 said weighed 154.1 gr and weighed them on the Redding scale. The results were;

154 gr (8)

154.05 gr (4)

154.1 gr (4)

154.15 gr (4)

As we see the GS-1500 did weigh them with a +/- .075. However the actual mean was closer to 154.075 than the 154.1 gr the Hornady GS-1500 weighed them at. Given that excellent level of consistency I doubt I'll fault the GS-1500!

Larry Gibson

[Larry Gibson]

popper

I guess if all you shoot is 50 yards then you're doing as good "consistently" as you want. It's really counter productive to try to determine accuracy for longer range shooting based on such short range testing. Dispersion is a function of range, especially with imbalanced and inconsistent bullets. Shooting at such short range demonstrates little other than you have an effective short range load. To claim accuracy (group size/dispersion) at longer range is unrealistic. As an example here is a test at 50, 100 and 200 yards with a load that was over the RPM Threshold demonstrating non linear group dispersion;

134137134139

Here is the same bullet in the same rifle loaded under the RPM Threshold. Note the linear group dispersion to 200 yards;

134141

Note the 4.25" group at 200 yards where we paid attention to consistency and kept the RPM under the RPM Threshold. That's a lot better where even with consistently cast bullets when we crossed the RPM Threshold the group size/dispersion increased to 14.5". Note with the 50 yard groups with either; both are quite satisfactory for a lot of close range shooting. However, only one of them is truly useful for longer range accurate shooting.

The difference between the two is why we do what we do to be consistent and to control the RPM.

Larry Gibson

[MBTcustom]

Most of us these days use an electronic scale to weight sort cast bullets. Electronic scales by necessity have a +/- accuracy range. I have tried several over the past years and have settled on the Hornady GS-1500 for my own use. It comes with a 100g calibration weight and is easy to use. Anytime the scale reads other than 0.00 when the bullet is taken off I recalibrate. That gives me as good as consistency as I've gotten and is better than with any other scale.

Another consideration for "consistency" is just how "consistent" is your electronic scale and that begs the question. I just completed weight sorting 531 linotype 30 XCBs. The GS-1500 has a "resolution" of .1 gr which I've come to realize is close to a .075 gr +/-. Where the acceptable range begins and ends is dependent on the median weight selected. Using a tried and true Redding balance scale which is zeroed and calibrated with certified weights on which I can read to .05 gr I decided to test 20 selected bullets from the batch just weight sorted. I randomly picked 20 out of the batch the GS-1500 said weighed 154.1 gr and weighed them on the Redding scale. The results were;

154 gr (8)

154.05 gr (4)

154.1 gr (4)

154.15 gr (4)

As we see the GS-1500 did weigh them with a +/- .075. However the actual mean was closer to 154.075 than the 154.1 gr the Hornady GS-1500 weighed them at. Given that excellent level of consistency I doubt I'll fault the GS-1500!

Larry Gibson

Great post Larry.
I use a cheap Frankford Arsenal digital scale. It is touted as having an accuracy of .1 grains (which I had to see to believe). After testing with standards, I found the accuracy of the scale is actually slightly better than +-.1 grains ie: definitely within .2 grains of indicated weight (amazingly accurate for what I paid for it).
It is sensitive to temperature, but I only run my bell curves when the shop temperature is levelized.

I agree completely with your statements above. Even with jacketed bullets, linear dispersion is never to be a forgone conclusion. I have made shots on game at distances longer than what I had tested, but I had a very good load with my 300 Win Mag that demonstrated linear dispersion from 50 to 100 to 150 to 200 yards (at 200 the group size was 1.5" and that is the limit of the local shooting range) and I felt on shaky ground taking a shot at 300 yards with that rifle and load.

It is much worse with cast bullets because non linear dispersion is very very common, and in fact, I assume that the bullets will go wild at distances past where I have tested them at, and I find I am correct in this assumption much more often than I am to the contrary.

Accuracy at distance with cast lead is pure skill with the pot, press and trigger, along with a very shrewd selection of components used for the task.

[Doc Highwall]

Here are two links to help you with your electronic scales and preventing them from drifting.

http://bulletin.accurateshooter.com/2015/03/tech-tip-reduce-electronic-scales-drift-with-anti-static-spray/

http://bulletin.accurateshooter.com/2009/11/inexpensive-noise-filter-helps-reduce-scale-drift-problems/

[MBTcustom]

One thought on the serious side, the 168 Sierria and it's other variant normally employ a small hollowpoint to produce a blanket of air to assist with the surface friction in the air, much like a boat hull in the water, wonder if the same would work for cast.

It does. My Accurate XCB bullet design (31-160G, cast by me, and HPed by me) was tested with and without a precision hollow point by Larry Gibson, and there was a positive measurable effect to the bullets modified to HP.

[kbstenberg]

Tim I think I am understanding the relation of bell curve and dertermining the better heat setting.
Is your second step in better casting.Then using one temp. bell curve the different time sequences in the casting process.
Am I correct in assuming the different timed periods in your casting system are.
A. Time taken for the sprue to solidify. (At what point in the solidification process do you cut the sprue?)
B. Time between the bullets are dropped and the mold is closed.
C. How long between closing the mold, and refilling it. I think that is what you call lag time.
I have learned that the timing of closing the SP has some bearing on how much heat is held in the mold.
My son made an app for the comp. to show continuous timing. So I have started using that rather than counting in my head.
The particular mold I am using doesn't let the sprue puddle stay in the molten state for more than a second before it freezes. I have taken the mold to a temp. of 400 and all bullets are to a heave frosting. At 390 deg. mold temp. the bullets come out 3/4 frosted. My pot temp is 720 deg. my alloy is COWW+ 2%sn.
If I tried using a melt temp. of say 730 to try to get a longer sprue liquidus state. And used a much longer time periods to offset the hotter melt temperature to keep the mold temp. down. Would you consider those changes to get your longer sprue liquidus times?

[MBTcustom]

Tim I think I am understanding the relation of bell curve and dertermining the better heat setting.
Is your second step in better casting.Then using one temp. bell curve the different time sequences in the casting process.
Am I correct in assuming the different timed periods in your casting system are.
A. Time taken for the sprue to solidify. (At what point in the solidification process do you cut the sprue?)
B. Time between the bullets are dropped and the mold is closed.
C. How long between closing the mold, and refilling it. I think that is what you call lag time.
I have learned that the timing of closing the SP has some bearing on how much heat is held in the mold.
My son made an app for the comp. to show continuous timing. So I have started using that rather than counting in my head.
The particular mold I am using doesn't let the sprue puddle stay in the molten state for more than a second before it freezes. I have taken the mold to a temp. of 400 and all bullets are to a heave frosting. At 390 deg. mold temp. the bullets come out 3/4 frosted. My pot temp is 720 deg. my alloy is COWW+ 2%sn.
If I tried using a melt temp. of say 730 to try to get a longer sprue liquidus state. And used a much longer time periods to offset the hotter melt temperature to keep the mold temp. down. Would you consider those changes to get your longer sprue liquidus times?



First, do not count in your head. If you check yourself against a clock, you will notice that you either count too fast, or too slow throughout a casting session. You need to use something that is more consistent.

Also, do not time each stage of the casting operation only (fill, cut, drop, close, dwell, refill, etc etc etc.) You need to be consistent in the total time it takes to complete all these tasks, regardless of whether you get a bullet stuck in a cavity, have to scratch your nose, drop your stick, lube your mold, leg breaks off your chair...... etc etc etc.

If you utilize this system and keep a completely open mind, you may find the most consistent point gives you plenty of freedom to time the entire cycle and it may be something you never would have figured on.
I watch the clock, and when I'm dialed in, the sprue plate opens at the same time @ 3 seconds, the bullets drop at the same time @ 5 seconds, (I allow myself time to look in the mold and check it for lead spatter (about 3 seconds)) and the mold is shut again @ 15 seconds.
How long I wait after shutting the mold is completely a function of the alloy/mold temperature relationship, and is set by the bell curves. When I'm casting with a mold, the mold is the boss, and it doesn't care what I or anybody on this forum thinks is right or wrong. I am not in charge of the casting operation, the mold is. I just work here.

I can tell you this, when I'm using an alloy similar to yours, with a certain brass two cavity mold, the pot temperature is set at 695 degrees, the mold is run at 450 degrees, and the entire cycle time from pour to pour is 30 seconds. That's what the mold likes. I never would have run at that cadence and temperature listening to the advice of other people, and that is not the same for all my molds. I would like to think that another brass mold of similar caliber and bullet weight, block size, and SP size, would run in a similar fashion, but I really won't even try to assume that it would. The bell curves will tell me soon enough what the exact combination should be.


Just watch your bell curves and try different things. It really doesn't take long to run several batches of 100 bullets in order to dial in a casting prescription, and you're getting lots of good practice like dry firing a target rifle in your living room to get trigger time.
Use a logical thought process, and constantly observe what you are doing. I time the entire cycle above all else, because I noticed I was dealing with this phenomenon that we all know and love called "tolerance stacking". I was trying to time each task precisely, and what I found was that my overall cycle time was varying wildly by as much as 10-15 seconds. I was working my tail off trying to micromanage the hell out of my operation, and I was only fooling myself.

Does that help, or did I misunderstand your question?

[kbstenberg]

Sorry about my thought and writing pattern.
Yes you answered my timing question completely. I thought each stage of casting was timing controlled.
With my mold producing heavy frosted bullets at 395. I am assuming that would be the hottest I should run it. Even though my sprue puddles don't stay liquidus for more than 1+ seconds? (let the mold tell you what it likes.)
I did up the melt temp. to 725 and got very little more additional time with the sprue puddle. But my bullet weight variation increased dramatically Kevin

[RogerDat]

Well thanks for the information and ideas!
If I can't measure in a manner that provides some guidance on what to change and a method for evaluation of the effect of that change then I'm just guessing.

I punch paper for fun, guess you could even say I shoot rocks but I have learned a couple of things over the years. Practice only makes perfect if you practice doing it perfect. Once a physical operation becomes very well practiced even done "casually" it is done more consistently.

Be it welding, driving a golf ball, or using power tools once you have developed a good technique even just taking a "whack" at doing it quick and dirty you will use that good technique and yield better results. Now I have to add a digital scale to my wish list but look forward to knowing the cast part of my effort is consistent, then I can more effectively gauge the difference powder load/type makes.

Just because I'm only shooting paper plates don't mean I want to miss.

[MBTcustom]

Paper plates are awesome. I've shot them for years with a 1" dot in the middle made with a sharpy marker. Give me a pack of paper plates, a marker and a staple gun, an I've got targets a-plenty.

A digital scale is a wonderful thing, and I have become quite fond of the Frankford arsenal model. IIRC they are on sale and (gasp) in stock at MidwayUSA right now.

The main problem with controlling your process, is that just controlling it will only get you so far. You have to find out how to do things "exactly" right, or you will be doing things "exactly" wrong.
It's the old "accuracy vs. precision" principle. You need both.
When I first started casting, I was neither accurate nor precise in my method. I started trying to improve myself, and only got so far because while I improved accuracy, I still lacked precision (one does not equal the other in front of a casting pot). So I was being a total control freak with my process, but I still had a broad bell curve.
This method, will take you from a point of precision with no accuracy, to a place where both shake hands to give you a nearly perfect casting prescription, and very impressive bell curves.
See this explanation of scientific accuracy vs. precision:

http://celebrating200years.noaa.gov/magazine/tct/accuracy_vs_precision.html

[MBTcustom]

Just an update, I now have an RCBS ProMelt casting pot given to me by a very kind forum member who I am building a rifle for.
I haven't been able to really rag it out yet, although Lars45 and I got to play with it a little last Sunday. Given the excellent design of this pot and the apparent uniformity of the spout, I think this may take my pursuit of consistency to the next level. I'll post when I have a chance to rag out his awesome new piece of equipment.

[SgtDog0311]

I'm not a high velocity shooter but still find this thread very interesting. I frequently, if not always, do a bell curve of my casting sessions just to see how I'm doing with my mold and casting technique, and as a method for further cull. More time than most would spend but there it is; I've only been casting a few years so lots to learn!!

If I ever get to plus or minus .02 I'd consider myself "accomplished". Most my caliber/curves will be anywhere from .07 spread to 1.5 spread. Size of the bullet makes me use a longer piece of tape:-) Even with a single cavity I've not made any skyscrapers.

So, I'm not posting the pic to brag (obviously) but to illustrate advice Green Lizzard gave me once concerning two cavity molds. The point is made pretty well here and that is: if you don't mark cavities when two cavity molds drop different weights will pose a problem where the curve from each overlap.

How do you know when a bullet from the heavier cavity drops down into the range of your lighter cavity if they are not marked somehow? This illustrates the problem fairly well. Looks like my cavities drop about .07 of a grain difference in weight (numbers would be pretty equal except 50 from the lighter cavity are being pan lubed).

Then again, maybe the cavities are equal and my technique actually sucks that bad:-) Regardless I'll shoot all but the outside two columns and treat these as two .5gr-.6gr spreads.
136431

[Sticky]

I need to mark my molds as you mentioned John. I have all multi cavity molds, most are 4 cav, a couple of 2 cav for rifle boolits, but I am sure that this is causing me some variance in my curves due to the individual variances from cavity to cavity.

I have been working with my mold and alloy temps, learning to time myself and it is helping (though I still have a LOT to learn) with better consistency in my casting sessions. I am getting much closer to a consistent +/- 0.5gr, want to get it down a couple tenths on either end, but with multi cav molds, I do have some challenges to face. Live and learn.. LOL

This thread has been helping me immensely! Thanks goodsteel!!

[Blackwater]

This thread really needs a sticky on it. Administrators?

[popper]

Cast a bunch of the 31-142C plain base - 2C Al. this morning, @ 700f, same alloy as before when I tried 720 & 680F. 21 culls of 108, 3 were bad pours (me, no real base), 2 had the bad drive band spot, the rest were just slightly rounded base. Then I tried leaving the mould & plate open longer ( a really fast count of 8) - 15 of 80 culls. 4 bad pours, 1 bad drive band and the rest rounded base. BUT - sprue cuts were really hard with gloved hand and sprue cooled faster than the base so base dimple was huge. All were still frosty in the middle. I did find 'dragging' from one to the other cavity gave poorer results, same as I found for the slotted plate. No 'purging' of the spout, no bad noses. I 'broke' the top edge of the mould last week to help venting, only the pivot side cavity seems to throw the bad spot now. Still have to figure out why I get so many rounded bases but i insect pretty good no no real big deal. No I don't plan on weighing them. Last batch did 1 1/2" @ 100, 1750 fps. Will sorting make a difference @ 2-300, possibly.

[David2011]

When I wrote this I was at the end of page 4 of 8. This has to be the best single thread on casting I've ever read. I've been casting since the early '80s and still learn constantly. The contributions here are from the people I consider the rock stars of CastBoolits. I know Tim is a first class act.

Casting tonight, I stumbled across something new to me. I've always poured with a generous stream out of a bottom pour RCBS Pro-Melt. I was trying to empty the pot to clean the rod and spout. The lower the lead got the smaller the stream got and the better my boolits got. The mold temp was easier to control and even though it took longer to fill each 158 grain cavity, the pace went up because the mold wasn't getting as hot. I have to try restricting the flow with a full pot to make sure there wasn't something going on with the melt temperature before making too many conclusions but the slower pour seemed to make much better boolits. The wait between refills was reduced to literally nothing. I was using a 6 cavity Lee .38 mold which I find much more difficult to use than Lyman, RCBS and SAECO iron or leaded steel molds. Production was so much better with the small stream I couldn't believe it.

Thanks for the great thread, Tim

David

[MBTcustom]

You're welcome David, but just remember, every mold is different with different preferences, and spout flow is another thing that has a sweet spot.
I just got an RCBS Promelt compliments of Jayvod, and I'm still getting used to it. My little Lee 4-20 was very consistent in pour from 3/4 full to 1/2 full, and I have no doubt the RCBS will be the same. There's just no way around it.
However, the RCBS just seems to have a lot more pressure on the stream. I can adjust it down, but then, I'm not filling the cavities very fast.
I'm still playing with it. I only cast on Sundays, and last Sunday I put a Lee two cavity 500 S&W mold through it's paces. That, my friend, is a beer keg of a bullet! Since it was for a friend's handgun, all I was concerned with was physical appearance on the first batch.
The first run was pretty rough with a 30 second cycle time. I think that little Lee mold had more lead in it than aluminum after it was filled! I dumped all the bullets back in the pot and cast again, but this time with a 1 minute cycle time. That made good looking bullets.
This Sunday, I'm going back in and I will start plotting bell curves with the bullets and see where and exactly how the mold likes to run.
Honestly though, this ProMelt was a veritable atomic bomb to my process (even though it's all that and a bag of chips!). I'm hoping that all the dope I figured out for my molds with the Lee pot is still good for the ProMelt!

[popper]

Cast 10# of 9mm RNFP BB tonite, 4C Al. mould. Had the same problem of poor base fillout, frosty rounded base, running at 700F. Slowed the pour stream down to just more than a trickle and problem went away. I could actually watch the cavity fill and the puddle form. :Bright idea: Alloy is more fluid at higher temperature, flows faster! Pouring too fast and the sprue puddle fills - plugging up flow AND/OR cutting off the venting under the plate. When casting the 140 30 cal I noticed bases were worse at high temp but weight consistency (of good ones) was better (720 vs 680). I modded the Lee pot with a tap handle on the stem and had only poured the 140s since. Problem solved. Lower temp of 680 made the sprue cut very hard to time & IMHO gave tilted cuts so more weight variance.

[popper]

Cleaned the pot, adjusted the spout and poured ~850 for the BO with Isocore I ingoted yesterday. 700F - 53 culls, mostly slightly rounded base. 11% culled, 2 with the bad rear band, several incomplete bases - my fault. Cuts were clean with no pimples or divits. For the weight & clock watchers, I weighed ~ 50. 1 -140, 9 - 139.4-5, most were 139.7-8. Tossed one at 139.0. I'll try 710 next time as the sprue cooled fast. Puddle only filled the bevel.
Time to take a nap after cutting a bunch of live oak branches that were overhanging.

[popper]

Poured a bunch more for the BO. @ 710F, 17 bad, one was me, reject rate way down now :D. Weighed some good and bad (slight rounded base, divit in drive band, etc.) Same spread as before - for good and bad. Sprue cuts were great on all. Big HiTek session coming up.
Edit: For this mould ( & alloy) I found the temp sweet spot - 710F. 700 & 720 gave bad bases. Pour rate was just as sensitive - too slow, smiley faces, too fast - bad bases. I don't watch the clock but do watch the sprue and pay attention to the cut - whatever makes the 'cut' just right. Gone from 50% rejects to 4% for this mould.

[fivefang]

Hi & thank you Larry & Tim both for the fine information,but we all must stay aware of that some of us drive 25 yr. old pickups ,while others do not, so,the $ aspect comes in!shoot what metal you can afford,& learn all you can from those that have the $ means to teach, many thank for your time & efforts,now for tc 9w. gc's

[MBTcustom]

I love this thread. Rarely have I given so much information in one spot. I feel I have explained my position as thoroughly as my vocabulary will allow me to, and those that are looking to advance have easy access to clearly written information.
There is nothing else I can add without being redundant. I hope it helps people get where they are trying to go.

[Maximumbob54]

I would just like to thank Goodsteel and all that positively added to this thread. I tried a couple of the suggested changes last night in a short batch. I cast a lot of bulk blasting bullets from 6 cavity Lee molds and I usually see tearing from the sprue. It doesn't bother me much as they are just for 25 yards and in blasting fun but it wouldn't hurt any for them to be made better. Just slowing down and watching the clock to set the rhythm of the casting I hardly tore any of the bases. I have a small stash of Roto Metals and MBC ingots set aside for an upcoming project. The notes I've written down will all go into effect once I start using the "excellent alloy" but even the range scrap blasting will start seeing these improvements. Thanks to all!!!

[Chris C]

WHEW!!!!! goodsteel, you and sgt. mike have my brain buzzing. SgtDog0311 turned me on to the bell curve concept a couple of years ago. I've just started casting (yesterday in fact) but have used it over the years sorting commercial bullets for my target work. However, I don't have a digital grain scale and had been sorting them with a digital gram scale. When I cast my first 145 bullets yesterday, I was very pleased with how many weighed the same. 85 weighed 15.9 grm and 39 weighed 16 grm. But curiosity got the best of me today and I sat down at my beam scale and weighed them out............laboriously, one by one. Very disappointing............but probably typical for a beginner. I only had 22 that had the same weight, and there were no more to add within the +or- .1 gr range. Their weight varied from 243.3 gr to 247.9 gr. The largest number were 246.6 gr. So guess I can quit patting myself on the back. Obviously, I've a lot to learn about consistency. Thanks for starting the thread and for all who have continued it. Whew! Lot's to learn on my part.

[OS OK]

Thanks goodsteel...for the detailed information. It was informative, detailed and factual…mostly...well written and easy to read and follow. My first curve looked like the 'rolling hill country' in west Texas, now more resembles the 'Sierras' here where I live. You gave me a new tool and I appreciate it.

Charlie

[stu1ritter]

Tim, I only just found this thread, ran to the reloading bench and bell curved a random 100 of my last casting. Holy Cow. It is time to learn some consistency. I'd like to thank you and all the other posters for a most interesting and enlightening thread.
Stu

[Chris C]

Stu, I know what you mean. Really shocked me. I'd been using my "gram" scale to run bell curves because I didn't have an electronic grain scale............and didn't want to bother with using my balance beam scale to weigh all my boolits one at a time. Boy was I ever surprised when I took some "known" bullets that all weighed the same grams and put them on my new RCBS electronic grain scale. My bullets were all over the place. Guess I've a ton to learn about consistency!!! Just shows what one can learn sittin' in front of a computer monitor. :coffeecom

[stu1ritter]

This has indeed been eye opening. I took 100 of 150gr. WC from inventory and curved them, that's chart 1. This afternoon I applied Tim's technique of running 1 second of lead before filling the mold, no other change to my casting technique, lead temps, or anything, just the pre-run............photo 2. Photo 3 is the bullet stack for chart 2. I think this is going to be a great learning tool.
Stu
http://tinyurl.com/hogftoo
http://tinyurl.com/jg7f92h
http://tinyurl.com/zm653o7

[popper]

Cast another batch of BO PB 145s, Al. 2x mould. I preheat on a hot plate but found dipping the SP in the melt gets it to good temp faster. I cut with gloved hand and found by feel that I get better boolits when it 'pops' when cutting. Too long and the base gets crooked, too early pulls divits from the base. Curious, I weighed with and without divits - difference is NOT from divits! My normal ES for visually good boolits is ~1gr. I calipered a few and believe now the difference is from cooled mould temp variation/dia. of boolits - alloy temp is PID controlled. Toward the end of the batch I tried letting the mould cool more (after sprue cut), they seemed to drop easier with only one handle tap vs 2 or 3. They all went in one pile so didn't check dia. variation. More testing later.

[popper]

Wife made jello last nite which got me thinking - I know, bad. Why does jello usually (and not often) get bubbles only on top? This is in reference to voids in cast boolits everyone so carefully weighs to find. Answer is obvious, it cools slowly and allows air bubbles to escape. Yes, I've seen pics of voids others have found - they can exist - and are about the size of #7 shot. Many suggest an alloy temp 100F above solidus temp but I feel it should be maybe 150F above to allow slower cooling.
edit:single 7 1/2 shot is 1.2gr. and 0.091 dia ERROR in calculations My hypothesis - you can't cull voids by weighing unless they are really large. You've visually rejected 'bad' ones, does that 0.0005 really make any difference in accuracy? I will NOT contest the idea of weighing to become a better caster.

[popper]

Read the 'spark-range' test of 223 yesterday, where they purposely create wobble and watch how long it takes to dampen due to aerodynamics of bullet. 100 yds! for a 'good' bullet design. Wobble creats the circular pattern on the target we see, due to cyclodal spiral path to target. Wonder if they have test data for the profile we shoot. I consider the 'void' of the previous post as LARGE for 30 cal, consider the 'shot' rotating around the CG with a 1/4" torque arm (creating wobble). Worst case would be that void on the outside near the base - I tested in 40SW and got IIRC a 5" ring of holes at 10 yds. Gyro stability formulas show SF is proportional to the SQUARE of difference in twist. Yup, twist does affect our unbalanced boolits. And base divits don't make much difference, gyro wise. Why this long trieste? IMHO it is the quality of the pour that determines the boolit quality. Like I mean WHEN IT COMES OUT OF THE SPOUT! Dribbles, crooked flow (crud in the spout), too fast or slow, DIRTY alloy. So far I haven't worried about frozen drips - nose defects have less effect than base - and the drips get remelted by the pour anyway. It's all about 'venting' the pour. Cast on.

[popper]

Correct an earlier error. 1.2gr shot 0.091" dia. Volume=0.00315 cu. ". Surface area 3.15" 30cal 0.6" long boolit (approx due to boolit real shape), Surface area = .729 sq. ". 0.001" dia. dif = 0.000729 cu. ", 0.004" dia. diff = 0.00292 cu. " volume. So, 0.004-5" dia difference is ~1gr. of lead. Confirm earlier hypothesis, weight difference is PRIMARILY due to dia. difference - which is due to casting tolerance (i.e. consistency). Now the real question. How does weight difference affect accuracy. Small variation in velocity? Doubt you could measure it. No change in stability factor. Difference in the amount of lube/boolit? Maybe. Difference in sizing due too bore - probably. Where does that in-compressible lead go? Into the lube grooves and base! Maybe boolit is now 'unbalanced'. Just some musings.
With consistent melt and mould temp the dia. variation should be minimum - therefore previous 'consistence' statements are valid. Boolits will be more consistent, is it worth the trouble? To become a better caster - yes. On the target? Maybe.