Boolit Quality Control

[BABore]

Is their a set +/- tolerance on boolit weight that is deemed a standard? As a new caster I couldn't wait to stuff some in cases and go shooting. I visually sorted my boolits for complete fillout, good bases, and no external crap. My #311041 dual cavity drops good boolits right out of the gates. My #457643 mold takes some warming up and good bases are a struggle sometimes. All boolits are ladle cast with WW's + 1% tin. Anyway, the 311's shot great out of my '06, the 457's were good but had some wild flyers.

I casted up some fresh samples of each and sat in front of the POI RCBS 510 scale for a look. Out of 40 #457643 boolits, 20 were at 422.7+/- 0.2 grains. Six or seven were at 423.2+/- 0.1 and 15 were at 422.3+/- 0.1. Eight boolits were way low at around 420.5 grains. I know the light boolits probably had some internal voids or slag. Only one of the eight had and external flaw that missed the first visual.

I weight sorted 110 #311041 boolits. Seventy of them were 176.35+/- 0.15 grains. The extreme spread for 108 boolits was 0.4 grains. There were 2 boolits that were way light. Overall, pretty decent for a two cavity mind, I think.

How do you experienced casters inspect your boolits and what do you find acceptable for general use, not match stuff?

Oh yeah, I think I'm going to be in the market for a digital scale soon. :)

[felix]

BAB, you are asking a loaded question here. It all depends on the match specs. Example: BR or Military? Offhand vs Rest? 100 or 300 or 800? Slow, Timed, or Rapid?

What is most important is where the boolit imbalances are. More in the center of the boolit, or more towards the edges? Whatever, I usually go for plus or minus 0.2 grains for all shootables. Plus or minus 0.1 for alloy testing in a BR gun. Plus or minus 0.0 for 200 yard shotgun shell targets, or smaller, at more than 150 yards in a BR gun.

A balance manual scale I think is better because you can select the boolit on the scale's swing.

felix

[Junior1942]

I do a visual sort first, and I then weight sort by Standard Deviation. For normal work, +- 2 SD or even 3 SD is fine. For target work, +- 1 SD.

[BruceB]

BA;

I'd say the uniformity of your boolits is excellent.

As a general rule, I find that my bullets in the 200-grain range typically show less than one grain extreme weight spread, the 130-180s usually a bit less than that, and my heavyweights of 350-500 grains are also back into the one-grain-spread area, probably because they're cast in single-cavity moulds. Your results seem very similar.

Note that some of my rifle boolits are cast in 4-cavity moulds, and the low weight spread speaks well for the mould quality....at least, I think so. All my bullets are bottom-poured from an RCBS pot.

A digital scale is a huge blessing for weighing bullets, as my PACT takes only three or four seconds per bullet (if that!) to get a steady reading.

A few large-quantity weighing sessions with different bullet designs might be a valuable experience when first trying to find what sort of variation a caster is dealing with, or perhaps when beginning casting with a new mould. It would establish a reference benchmark of sorts for future production or acquisition of different moulds.

I don't normally weigh bullets, but I'm cogitating about that here lately. If I do decide to start weighing, I wouldn't worry in the least about bullets HEAVIER than average, unless they show finning or other deformations. What I would do is establish an average weight on a sample of about twenty bullets, and then just reject anything that was more than....what? One grain or 1.5 grains LIGHTER than average? That would definitely cull anything with hidden voids. Essentially, I think a grain or so of extreme spread is meaninglessfor most purposes. If a big match was coming up, then I'd weigh and sort to a half-grain, maybe, but that's about it.

Sorting this way also works very quickly with a regular balance-beam scale. Set it at your desired minimum weight, or just slightly below that figure, and just reject everything that fails to lift the scale's beam off the peg. Sorting to the tenth of a grain is WWAAAAAYYYY too anal for my taste!

[BABore]

That's pretty much how I set up my RCBS scale. Weighed 12 random picks, tossed out the high and low, then calculated my average. I penciled in +/- marks on my scale from a mean bullet. If it takes 3 to 4 seconds for an electronic, I may stick with my balance beam. Felix is right, you can pick them even quicker once you study the swing. I went a little slower and cherry picked ones that were exact for load developement.

I kind of suspect my wild flyers were caused by the powder that I was initally using. I was using some data from Greg Mushial, at gmdr.com, for a plinker load in my 450 Marlin. I was using 11 to 13 grs of WW 231. Groups at 100 yds were ragged holes with flyers that went 12 to 18 inches out. If I try that load again, I'll pay attention to powder position to see if it helps. Now that some of the newness is gone, I'll be weight sorting all of my bullets.

One final dumb question. I'm using Lee Liquid Alox for lube. Two coats plus motor mica. All of the bullets were well coated and produced a light lube star with zero leading. Does a variance in the lube weight, added to the bullet, effect accuracy? I'm not talking about the lack of lube causing a different drag, but say having more lube on one side than the other causing an inbalance. I'm standing all bullets on their bases to dry.

[Bass Ackward]

Is their a set +/- tolerance on boolit weight that is deemed a standard?

BA,

I had a guy that said that it was possible to get 1" groups if he weighed and miced his bullets ahead of time. So to him this was worth it. Then he screwed up and asked me what I thought. I never said a word and handed him my rifle with bullets that were wrinkled and rounded at the bands, with some that were filled out. I could see the look on his face as he chambered them one by one. Then his expression changed by the fourth shot. He shot 3/4" for 5 shots. He didn't know what to say.

The answer to your question is only answerable by you. After you go to what ever lengths you "currently" think is appropriate, then load up and shoot some of the lesser quality and see what you think. This can be eye opening as to what extent you want to screen them.

Weight variations seems to be over emphasized by a lot of guys. Take the recommendation for a load of 16 gr / 2400 in any military case with a bullet from 180 to 220 grains. I never mold that bad. So with slower powders the effect looks like it is even less. Anymore, if a bullet sizes on the front band so that my seating depth remains constant for ignition and the base is square, boom, off they go.

[felix]

Yes, you can have a problem of lube flyoff at the wrong time, such as right at the muzzle. This very well could affect the direction of the pressure exit gasses. To check, just use a softer lube or less quantity of the one you are using if you have a multigroove boolit. No, lube is so much less in weight than lead, so much so that it does not even enter the equation once the boolit is in flight. An air hole in the wrong place within the boolit is most damaging for the lighter boolits, or heavier ones shot at longer ranges. ... felix

[BlueMoon]

What would cause a void or air pocket in a bullet? Temp not up, or filling mold too fast or slow, or is it just something that happens?

Bill

[StarMetal]

Felix,

If the bullet has a good base and there's no gas cutting, how does lube flying out of a lube groove at the bullet's exit from the muzzle have an effect on the direction of the pressure exit gas, when the gas is supposely behind the base?

Joe

[45 2.1]

What would cause a void or air pocket in a bullet? Temp not up, or filling mold too fast or slow, or is it just something that happens?Bill

Bill-
This is usually caused from turbulence in the lead coming into the mold cavity. This can be negated to some degree by useing a furnace and pouring the lead stream thru the sprue plate hole with out touching the sides to obstruct the hole. Us a thin stream when pouring to accomplish this. Proper alloy temperature is necessary also.

[felix]

Joe, a perfect base? With good swage/bump dies, yes, you can make them perfectly enough to compensate for any error prone base that might exist. Cast boolits without special support are seldom perfect enough, unless great strains are expended to make them thataway. That's beyond the "hobby" part of the hobby for most folks, including me. Might as well go to BR condom boolits, and that brings back high intensity memories from my BR days. ... felix

[45 2.1]

A good bullet that is fitted correctly and a good load with the necessary concentricity will give you more accuracy than you are able to use. Once you experience a gun/load combination like this, you will know what I mean.

[StarMetal]

Felix
I think you know what I meant, a base that doesn't have major flaws as to allow alot of gas cutting. Let's go a step further. Let's make it a gaschecked base. I see a test coming up. I'll take a hardlube and make a few bullets with the lube grooves filled up completely, Then take another batch and deliberately lube half the grooves all on one side. I'll take a rifle and bullet that I know to shoot good and see what we get. Boy, I'd love to have a high speed photo of a cast bullet coming out of the muzzle to see what the lube looks like on it.

Joe

[felix]

I ALWAYS use the accuracy a boolit can deliver within my personal demarcation. No swage or bump dies allowed. Only pot pour boolits. For a good lot of boolits, I just increase the range or decrease the target size. For poor boolits, well, they are for charging tin cans at 50 yards offhand. The only rejected boolits are those which don't fall into a regulated pile. A good lot contains no less than 90 percent takers. A whole lot is rejected when only 60 percent is good. Checking is done after about 50 boolits from only ONE pot of lead, no sprue return. ... felix

[NVcurmudgeon]

BA, Looks like others have pretty well covered the how-to of weighing boolits. I would like to address when NOT to weigh them. I shoot only milsurps or normal hunting rifles, and mostly for practice and plinking. For the occasional postal match on this board, or the Nevada Cast Bullet Shoots, I weigh all boolits. My standard is within the same half grain, and usually there is a large enough lot to be able to select castings from the heavier end of the range. The mould used for these matches has the two cavities marked with punch marks for separation. All this is an attempt to eliminate flyers-usually successful. (And I never, never weigh pistol boolits.) For all other uses, visual inspection is plenty good. Weighing boolits is one of those pursuits that is fascinating at first, but becomes very tiresome in short order, IMO. Mostly we're just having fun here!

[Willbird]

I do not know if any have read "Rifle Accuracy facts" by Harold Vaughn, Sinclairs has it.

Could get in trouble mentioning a BOOK again hehe.....but in there he built a device to spin a bullet inside a plexiglas chamber that was suspended from two field phone earpieces (speakers ? ) and thus he could check a bullet for imbalance. He used an oscilliscope to measure the output from the two speaker coils generated by the imbalanced bullet making the device wobble...the bullet floated and was spun in an air bearing is the best I can explain it.

He also used a simpler device that was like a little trapeze with a vee block to place the bullet in, he cast a shadow on the wall with part of the device (like an optical comparator) to magnify the position change caused by a bullet that was out of balance, one would index the bullet several times and see how it balanced.

The book is very fascinating....and he explores all kinds of dynamics (during the bullets travel from ctg. to muzzle, and beyond) in bullets, cartridge cases, barrels, actions, etc. It is a shame we couldnt get him into cast bullets :-)

The Author has quite a few credentials, one of them being solving the problem of how to make a large bullet filled with fluids accurate (bio and chem artillary projectiles)

Much of his theory and proof applies to any kind of projectile however and I would reccomend the book to anybody that enjoys learning stuff....he even explains how to build and calibrate your own pressure gun, shows how to take flash pictures of bullets in flight...all the cool stuff.

I see no reason why his high speed bullet spinner wouldnt work fine on sized and lubed cast bullets.

Bill

[grumble]

Curmudg -- "Mostly we're just having fun here!"

BINGO!! Couldn't agree more. I admire those folks willing to squeeze the last drop of accuracy out of their turnups, but that sure isn't my game. The more time I have to spend on a batch of boolits, the less enjoyment I get from using them.

Good enuff is good enuff for me. I'm biting my tounge (keyboard?) on the chrono controversy for the same reason. When this process quits being fun and starts being a dedicated search for perfection, that's when I'll find something else to do.

[45 2.1]

When this process quits being fun and starts being a dedicated search for perfection, that's when I'll find something else to do.

No such thing with cast, unless you blueprint rifle, swage bullets, throat with swager reamer, etc. not to mention weather related problems. Bench rest is not fun when everything depends just on your ability to wind dope and not on your equipment.These problems are what makes it interesting!!!!!!!

[sundog]

Most of my boolits are subject to nothing more than visual culling. If she ain't purdy, she don't get asked to the dance. Problem with that is that some of the purdy ones got the personality of a box of racks. So be it. BUT, if you enjoy competing, such as I do in the military bolt matches, it is imperative to induce more consistency into the process. How much? Well, enough that it is still fun.

To that end, I guess I could write a small book covering, "in search of the no flyer group" (and no, I don't want to because it wouldn't be fun). Have I accomplised that? Yes, mostly. Am I still having fun? Yes. I will say this, however. If I had to do this tedious 0.1 grain culling for everthang, it wouldn't happen!

So, if'n yer fun meter pegs out and yer not hittin' crap, well yer still having fun. But, if it's fun to shoot consistent 2 inch groups at a hunert with cast boolits in a rack grade 03, well, knock yer socks off!

I will say this though. It seems the smaller the caliber (or group), the better the culling needs to be to get good shooting. You decide how much time to invest. Of course there's always the blind pig routine although that doesn't come along too very often....

Kinda like the old briefs or boxers deal. Depends. sundog

[Magnum Mike]

My opinion (and what i have used as a basis for my quality requirements) is (was) to weigh factory condom bullets and get the "range" of variability that they allow. I know from past experience with condom bullets that some are more accurate than others, i have weighed them both (and honestly they werent 1k bullet samples) but i got a range and have used that as a guide. With those guide lines in place, i have shot groups and determined that those "guide lines" are more than satisfactory for exceptional accuracy!

[BABore]

Didn't mean to get all you old boolit casting fart's all wound up. :)

I'm just a shooter/hunter too. The closest that I've been to a match is driving by. All my rifles are tried and true hunting rifles, but like someone famous once said "only accurate rifles are interesting".

Being a newbie, I hope to eliminate any poor casting technique through a little judicious quality control, i.e. weight sorting. Once established I'm hoping to reduce this to weight sorting for my heat treated hunting rounds and bragging groups. Everything else will be just plinkers.

My biggest challenge with this new hobbie is reloading them new shiny bullets. I've been sucessfully reloading for 25 years with store bought jacketed bullets and book loads. Now I'm contending with my own bullets and slimmer data sources. Never had to worry about the bullets weight variance with jacketed. Just one more variable to deal with. Look forward to lots of fun and learning.

[sundog]

BABore, alot funner doing it this way. Isn't it?

I'll take the "old boolit casting fart's" remark as a definite compliment! I know for a FACT that at least several on this board fit the description. HAR! sundog

[buck1]

I started putting my Rifle boolits to the scale. I found some bad ones that way. Also groups shrank. I use the +/- 1 tenth from the same cav. Flyers all but stoped and groups shrank. Its fast and easy, on a digi scale. ...Buck

[grumble]

I take great offense at the "old boolit casting fart's" remark. I've never in my life cast an old boolit. Harrumph.

[felix]

BR boolits are seldom exact in weight, but they are in swaging pressure. If the swaging pressure is light, it could mean the base area has an air pocket! If the air pocket is at the point of the boolit, there would be no accuracy problem. But, nobody wants to pay to find out, so the boolit is rejected. This is why your best boolits are swaged at home by someone with ultra sensitivity in their hand/arm. Most likely the family female of choice. Maybe an "old fart" would have the necessary arm strength requirement as well! ... felix

[StarMetal]

Curmudgeon

Exactly, I was very satisfied with my cast bullet shooting without doing any of the benchrest tricks. Just cast them visually inspection, load them, shoot them.

Grumble

When this process quits being fun and starts being a dedicated search for perfection, that's when I'll find something else to do.

We're already here on this forum. It's gotten down to rocket science now. You had better be an Albert Einstein in all fields before posting something technical here.

Joe

[StarMetal]

Speaking of old farts:

THE ANTICIPATED FART: This one warns that it is back there waiting for some time before it arrives. A person who is uneasy for a time in a crowd and who later farts at a time when they think no one will notice has farted an Anticipated Fart.

THE BARN OWL FART: A familiarity with owl calls is helpful in identifying this fart. If you hear a fart that has about eight notes in it, ending on a couple of down notes, and it sounds maniacal, you have heard the rare Barn Owl Fart.

THE BULLET FART: Its single and most pronounced diagnostic characteristic is its sound. It sounds like a rifle shot. The farter can be said to have snapped it off. It can startle spectators and farter alike. Fairly common following the eating of the more common fart foods, such as beans.

THE COMMAND FART: This fart differs from the Anticipated Fart in that it can be held for long periods of time waiting for the right moment. Unlike the Anticipated Fart, it is intended to be noticed. Harold Tabor recently held a Command Fart for the whole period in history class and let it go right at the end when the teacher asked if there were any questions.

THE DUD FART: The Dud Fart is not really a fart at all. ItÃÂ*s a fart that fails. For this reason it is strictly a group one identification fart, because there is no real way you can identify a fart that somebody else expected to fart but didnÃÂ*t. It is the most private of all farts. In most cases the farter usually feels a little disappointed.

THE OH MY GOD FART: This is the most awful and dreadful stinking of all farts - a fart that smells like a month-old rotten egg - as the Oh My God Fart. If you should ever encounter it, however, you may first want to say, oh ****, which would be understandable.

THE RAMBLING PHADUKA FART: You must not be fooled by its pretty-sounding name, as this is one of the most frightening of all farts. It is frightening to farter and spectator alike. It has a sound of pain to it. What is most diagnostic about it, however, is its length. It is the longest-lasting fart there is. It will sometimes leave the farter unable to speak. As though he has had the wind knocked out of him. A strong, loud, wavering fart, it goes on for at leas

THE TEFLON FART: Slips out without a sound and no strain at all. A very good fart in situations where you would rather not fart at all. You can be talking to someone and not miss saying a word. If the wind is right he will never know.

[grumble]

Joe -- "It's gotten down to rocket science now. You had better be an Albert Einstein in all fields before posting something technical here."

Aw, shucks. We don' mess with moroons like ol' Albert. Want teknikal? Ah kin shuck a rabbit in 14 seconds flat.

[Scrounger]

Joe -- "It's gotten down to rocket science now. You had better be an Albert Einstein in all fields before posting something technical here."

Aw, shucks. We don' mess with moroons like ol' Albert. Want teknikal? Ah kin shuck a rabbit in 14 seconds flat.

Piker! CarpetMan can skin a cat in nothing flat...

[Oldfeller]

Now, now gentlemen, you are all being "odd" again.

The new persons above were having a perfectly PC discussion on weighting bullets so they can shoot "more accurately" and now you old reprobates are discussing how they are farting in the bathtub and sniffing the bubbles.

How does this sort of "odd" behaviour add any value to the conversation?

Indeed, it could be taken that you could possibly be poking fun at the need for one-tenth-grain bullet sorting and that it is really non-essential to anything other than maybe a Dan mold contest.

But sometimes there ARE Dan contests (and other forms of VERY IMPORTANT shooting matches) which may require some extreme sorts of anal behavior.

One must not poke fun at questions like this unless one has NEVER sorted their bullets with a weight scale for any reason -- such is not ethical on your part. I have machined installed gas check and weighted the results so I certainly can cast no stones here in this conversation.

I have also sorted bullets into 3 grain spread groupings and shot them up by the little groups (not that it helped any mind you, but I thought it mighta could).

Now, having said that bullet sorting isn't the biggest bang for the buck effort-wise, what is?

Biggest accuracy improver I can relate to is buying a good rifle clamping stand to keep your gun from changing its cant angle from shot to shot (plus taking as much of the old fart effects out of it as possible).

Shame on you all for poking fun at a serious question like this. The technical term for such odd behavior is "fwerping" which is the Oxford English Dictionary's term for creating bubble bath bubbles from your other end.

Such bubbles should NOT be left still loaded for the next occupant of the tub. SWIMBO does NOT appreciate the change in ambiance from rose-lilac to dead possum that occurs when settling her head back down into such-like bubbles.

She will NOT accept that it was "accidental" -- she knows you too well.

<grin>

Oddfeller

[wills]

Quote from

http://www.riflemagazine.com//magazine/article.cfm?tocid=685&magid=52

“One last measuring device was covered in full two issues ago, in Handloader No. 213 (“Balanced Bullets,� October 2001). Vern Juenke’s ultrasound bullet machine has become almost as indispensable to my loading as case-spinning tools. For those who missed the original piece, Vern’s machine measures the interior concentricity of any jacketed bullet - and explains a lot about those mysterious fliers that show up in otherwise consistent groups.
Since the article appeared several friends have bought the unit (which runs $660), and called to say, “Gosh, John, it works!� It was hard to find Vern for awhile, since his phone company had changed the local area code and evidently refused to tell anybody. But if you’re interested, he’s still cranking out Internal Capacity Comparators at The Accuracy Den, 25 Bitterbrush Road, Reno NV 89523. These days, when I load ammunition with bullets sorted by the machine, into straight cases with neck-wall thickness varying no more than .001 inch, and the rifle doesn’t shoot, I know it’s the rifle, not the ammunition�

[grumble]

Wills, what we really need is an x-ray machine, possibly one that will have a USB interface to an ultrasound resonator. And, if you can find one that will do dynamic readings at, say, 100K RPM, we'll ALL buy one!

Babbage lives!!

[BlueMoon]

I've been playing around with casting my own bullets, off and on, for only four years or so and I started to weigh bullets to see what quality or how close in weight my bullets were. I read so many posts about people casting x amount of bullets with only a plus or minus of .3-.5 grains and I never have been able to do that. Also, I bought a BBk II electric scale that I decided I didn't trust to weigh powder with all the warm up and such.

I think if I ever learn how to cast a consistant lot of bullets, that I still want to look at-bases and bands, I will leave off the weighing. I'm just trying to find my way with equipment and experiance being added slowly. I really don't enjoy the weighing very much.

All my lots of ingots are a little different since I got 50lbs of monotype to add to my ww's, range scrap, and pure lead sheeting so maybe that's some of my problem to, although I've seperated them a little by hardness. But it seems that all of one pot of melt should put out bullets of about the same weight without having to stir the pot a lot, if I'm casting right.

Bill

[wills]

Wills, what we really need is an x-ray machine, possibly one that will have a USB interface to an ultrasound resonator. And, if you can find one that will do dynamic readings at, say, 100K RPM, we'll ALL buy one!

Babbage lives!!


Good idea. Should I happen across an article describing such, I will report back to the multitude.