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Castaway
05-02-2022, 07:23 AM
299700
This is why you should weigh your bullets. Four and one. One day, I’ll get five

sharps4590
05-02-2022, 08:40 AM
Shoot a fouling shot off to the side, then shoot for group....if the first shot was from a cold, clean barrel.

Castaway
05-02-2022, 08:47 AM
Flyer was 4th shot

indian joe
05-03-2022, 12:56 AM
299700
This is why you should weigh your bullets. Four and one. One day, I’ll get five

I know ya didnt flinch but that is exactly where mine go when I do - high and wide at 11oclock - can show a bunch of competition targets with one of the ten out there. I'm workin on it but aint happened yet!................

Castaway
05-03-2022, 07:47 AM
Possible flinch, but unlikely, was sand bagged in and called a good shot

sharps4590
05-03-2022, 07:55 AM
Flyer was 4th shot


Ha! I would not have suspected that.

Harter66
05-03-2022, 09:51 AM
I thought it was so you'd know your 27-130 weighed 141 gr dressed so you didn't drop primers when groups were closing and still 1 gr under max to keep closing them ........ New rifle needed to be proofed anyway .

I'll enter a guess of lube purge . Your running just a little too much or something is just too much of a good thing in your lube . Your pushing the excess out or riding over it . Either way the excess is pushed out or causes an uncontrolled base defect . Viola' bullet out . It's impressive that you have it down to the same round every time .

fastdadio
05-03-2022, 12:32 PM
299700
This is why you should weigh your bullets. Four and one. One day, I’ll get five

Izzat powder burns I see on that target? :kidding:
:bigsmyl2:

Castaway
05-03-2022, 12:54 PM
fastdadio, any powder would have had to travel 100 yards

KenH
05-03-2022, 01:19 PM
Powder burns on target? That's funny :)

Is it always the 4th shot that gives the flyer? If so, that's also interesting. BUT - my congrats on good shooting with a good "dialed in" rifle.

Castaway
05-03-2022, 01:43 PM
On a good day, I can get 5 at 1.75”, plus or minus w/o the flyer. I’m convinced the anomaly was due to a bad bullet. The above is the best I’ve ever done, by far. Flyers for me can happen anywhere in the string, there’s no pattern.

popper
05-03-2022, 02:39 PM
Interesting you think weighing bullets would catch bad ones. So a single grain of alloy is what volume? Say you have an air bubble and it gets compressed when firing. How much does it really distort the bullet? It will NOT throw that flyer! I shoot RNFP cast from an AR10 308w 2400 fast loads, some with nose deformation and don't get that large a dispersion. Long time ago I nicked the base of some 40sw, ~1k fps and saw a nice 4" circle of holes on the target. You either pulled it or had a damaged bullet, not a 1gr difference due to a void. Yes excessive lube can cause it.

Castaway
05-03-2022, 04:08 PM
Bad base makes sense but these were checked. Could a badly applied check or the check flying off cause it? The lube problem is new thing for me. I wipe a wet and dry patch between shots. Could a void in the grease groove cause a 4” flyer?

tmanbuckhunter
05-03-2022, 04:15 PM
I was getting the occassional flyer like this with my silhouette gun, shooting no neck tension. I finally let the "shoot with neck tension crowd" beat some sense into me and simply going to .001 neck tension stopped the flyers altogether. I don't know what your load is exactly, but just a thought. Only other thing that can cause that is an airpocket if you didn't flinch.

bangerjim
05-03-2022, 06:01 PM
The ONLY time I weight boolits is either with a new mold or I change the alloy mix drastically. Once I know the weight, I write it down on a slip of paper and put it in the mold storage box. End of weigh scale usage!

I am not one to weigh every boolit and worry about a flier or two. All the shooting I do plinking and target practice with water bottles and paper. That's all. No hunting. No match grade shooting, No contests. Only fun with friends. It's like a round of golf, the only competitor I have is MYSELF and MY SKILLS and not the people I am playing with or blaming the weight variation/accuracy of the clubs because there was blade of grass or tiny piece of dirt on the clubs or balls. It's all ME. :grin:

Your body movement/position or surrounding conditions/weather/wind will relate to good or bad shooting, not the tiny miniscule weight variances in boolits you cast.

Have fun

bangerjim :Fire:

Larry Gibson
05-04-2022, 10:31 AM
I see you've got the usual responses referencing that weight sorting isn't necessary. Well, for the usual 1 1/2 - 2 moa 3 or 5 shot groups most seem satisfied with weight sorting cast bullets isn't necessary, if you cast good quality bullets. Also as seen many just kiss off flyers such as yours as a twitch or bad shot even though the shot was called good. All that is fine and I shoot a lot of such bullet/loads in numerous rifles just for fun.

However, when I'm serious about getting the best accuracy then weight sorting is a must along with casting excellent (that's different from "good") bullets with a proven alloy. If you want the accuracy that the 4 shots show a potential for then I suggest you also weight sort.....properly. Here is a response i posted some time back that may give you some insightful information.

Weight Sort 30 XCB Cast Bullets


"For your theory, that lighter bullets in a batch are less accurate than the heavier ones we must assume: 1. that light bullets are caused by voids, 2. that those voids are not too near the longitudinal axis and, 3. that they are large enough to be significant."

Ergo is the problem in this discussion. I do not subscribe to any of those 3 assumptions. In fact if you re-read my post with the graph I explain what I've found to be the real problem and it is not the suspected or assumed "voids" in the bullets. Yes, that's what we've all been told for probably a hundred years and it is what we've based our testing on.

Ten years ago I thought I was casting pretty good bullets, excellent in fact. However. the more I got into shooting cast bullets at HV I found while I was casting good, excellent bullets I too hit the accuracy wall that joeb is alluding to. I also found that when those cast bullets were pushed to really HV (2500 - 3000+ fps) they did not do as well as expected. Back then I was weight sorting as we've all been told to. If you line them out by weight you get the so called "bell curve". In proving insanity I, like you and everyone else, then did the same testing of each .1 gr testing over and over again expecting different results.....we all got the same results; accuracy was not really improved via that method no matter how many times we ran the test. You are asking me now to run the same test and think I will come up with different results? It wouldn't happen.

Let's assume we have a mould that will cast perfectly even bullets in all dimensions. Not an assumption but fact is that mould has a finite capacity for any alloy. Thus if we cast with a good alloy giving the best fillout then only those that weigh the heaviest will have filled the mould out completely. Any bullets with less weight are then not dimensionally the same. We may not be able to measure other than weighing that difference but the difference is there in lighter weight bullets none the less. Now that difference in weight (mass) is there but it is not predictable.....we don't know where in or on the bullet that difference in weight is missing from. The missing weight is what creates the imbalance. I suspect voids in the alloy are not the problem but rather other aspects are which I have previously discussed.
I recently cast 542 NOE 30 XCB bullets of #2 alloy. I have just completed weight sorting them. In the next post I will show the graphed results of the weight sort which should aptly demonstrate what I'm saying. Have to copy, download, etc. so it will be an hour or so.

Here is the results of the weight sort. 542 bullets were cast of Lyman #2 alloy and WQ'd. They were then aged about 12 days before I got around to weight sorting. Here is my set up for weight sorting. I visually inspect each bullet for any defect. If any is found that bullet is rejected to be melted and recast at a later casting session. Those that pass my anal visual inspection then have any remnant of the sprue cut off. That is done on the lead block with a sharp blade on the pocket knife. The bullet is then weighed on the Redding balance beam scale. While waiting for the beam to settle I then visually examine and sprue cut another bullet. With the magnifier in front of the scale I can readily and accurately see what the weighed bullets exact weight is. The bullet is then placed in a bin for that weight.

Of the 542 bullets weighed 22 were rejected for a visual defect or because they weighed less than 156.9 gr which means the weighed ones had passed the visual inspection but still weighed way lite. The remaining 520 XCBs were weight sorted into separate bins of .1 gr increment from 156.9 gr to 158.0 gr......a 1.1 gr spread.

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Here is the rough graph of the weight sort. As you can see there is no "bell curve". The curve rises from 156.9 gr slowly to 157.5 gr and then rises sharply. The "curve" then plateaus out at 157.7, 157.8 and 157.9 gr with 113, 124 and 110 bullets for each weight. The "curve" then falls sharply to just 9 bullets at 158.0 gr. Of those 9 bullets only 2 actually weighed 158.0 gr. The remaining 7 bullets weighed between 157.9 and 188.0 gr. There were no bullets heavier than 158.0 gr.

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The weight sorting is showing us the 113 bullets of 157.7 gr, the 124 bullets of 157.8 gr and the 119 bullets (I'll put the 158.0 gr bullets in with those) of 159.9 gr weight has the highest weight/mass of alloy in them. Since the curve dropped off suddenly we see those weight bullets are the most consistent and the best the mould will produce with that alloy. Those 356 weight selected bullets will be used for best accuracy.

The 157.6 gr bullets will be used as fouler/sighters as I expect they will give very good accuracy also given only a .2 gr +/- difference in weight.

Had we lumped all the visually selected bullets into one group 70% would have been with the excellent bullets, another 15% would have been with the fouler/sighter bullets and the remaining 15% would have been with bullets having a weight/mass difference of 1.1 gr. Now, had I done that I probably would have got nice 1 1/2 moa groups with 7 +/- shots going into moa or less and 2 -3 +/- shots going out of the group in the 1 1/2 moa +/-. How many of you shoot groups like that with bullets only visually sorted?
It is with such weight sorted selected bullets (the 157.7 to 157.9 gr bullets) that I am able to hold moa accuracy to 300 yards and beyond with a 2900+ fps velocity.

That is how I weight sort and why it makes a difference.

With such weight sorting I am able to consistently shoot 5 and 10 shot groups shown here even though I was shooting for score on the CBA target not group. Lower left target is sighter target. Bottom right target (the 10 shot group) is actually 2 different 5 shot groups. A wind came up out of 4-5 o'clock and I did not correct for it as I wanted to see how much it affected the bullet. The group enlargement toward 9 o'clock is the result.

299766

high standard 40
05-04-2022, 11:02 AM
Larry, I use the same process you do. It has served me well. We don't all have the same accuracy requirements. But I have found weight sorting to be a valuable tool to achieve optimal accuracy.

Harter66
05-04-2022, 11:54 AM
In the vein of weigh sorting . I had a rifle that with a 1.5 gr difference in case weight , single source of brass , I water weighed too , that would not just toss one out but put it in a group of its own 18" away . This wasn't some high end precision $5000 rifle either it was a plain Jane left hand 1965 Savage 06' .

indian joe
05-05-2022, 09:09 AM
Not shooting the kind of groups these other blokes are but I want to eliminate every excuse I possibly can
I weigh sort boolits any time I am serious - got a neat little digital scale and the job got a lot easier and quicker - as I proceed I stand em up in their weight groups on a flat board right near the weigh station - line em up in rows of 10 - 20 front to back -

so I have a lead boolit graph grows as I go along - definitely agree with Larry - no sign of a bell curve !!

Also think that a part of the variation in mine is coming from how I hold the mold (how hard do ya squeeze the handles as you pour) I get about 5% are well outside the average, (got slack on the handles and they are fatter or sprue plate screw came loose and we decided to pour a few more before fixing it - just dumb stuff)
Quality brass mold (CBE) gets me about half the variation in the main batch that I get with a LEE (difference between $25 and $150 or difference between aluminium and brass?) - not a pick on LEE - cant beat em value for money and they work good for a lot of shooting.

No bell curve at my place!

freedom475
05-06-2022, 10:03 AM
Bad base makes sense but these were checked. Could a badly applied check or the check flying off cause it?

Well I believe that this is your answer...Yes, a gas check poorly applied, or flying off during flight is not good for accuracy. Most BPCR matches that I am familiar with do not allow the use of Gas-checks. Annealing the checks might help, but using a mold that does not require them will be best.

Lead pot
05-06-2022, 12:17 PM
Larry,

You make some good posts with your cast bullet information.
I'm very annal with my cast bullets because I shoot most matches at long range and for this purpose you need to spend time getting the proper alloy and put that alloy in a mould casting a good bullet.
I have spent a lot of research time with alloys that will hold the bullet from getting setback that will result in bad accuracy if the operation gets moved out of balance.
Most of my shooting is with bullets 500 grains plus and the the way I cast I seldom get a bullet under one grain light from the heaviest when ever I weigh them, seldom do I do that :D
What I found causes some of the light/heavy variances is dross getting into the cavity from the ladle spigot. I have split light bullets to see the voids and all I have ever found is dross.
Also I found that improper mixing the alloy. Tin is light or if one uses ww a the lead mix the WW are lighter than the lead and if you don't get the mix blended you could pick up the lighter or heavier mix and the results will be weight variance. I mixed alloy in the 20# Wagge lead pot with just dropping the lead tin ingots and storing it with a spoon a few times with flux and I found perfectly cast bullets weighing as much different as 1. 7 grains.
The next batch was mixed with the same amount of lead/tin by weight but I used a paint mixer you put on a drill motor and I mixed and fluxed that pot using it for a longer time frame and cast a bunch of bullets and only 3 out of 50 went a 1/2 grain light from the heaviest. I don't know if a proper mix does this or not but I spend the extra time doing it.
A sprue plate to loose will cause heavy or light even when properly filled mould.
When you get bullets like this after they leave the muzzle looking like this.
299910

The results should look like this if you do your part behind the buttplate and find the proper powder load.
The first two targets were ladder loads at 100 yards and the small target was a follow up test at 200 yards.
A cast bullet will shoot well if all components come together properly.
Just don't push them to hard :D

299902299903299904299896[/attach[attach=config]299895299897[/attach[ATTACH=CONFIG]299912

Castaway
05-06-2022, 03:24 PM
I have a nose-pour Hoch mould that does well, but the group above was with a Lee 500 grain Govt style bullet.

HWooldridge
05-06-2022, 03:38 PM
The reason nobody charts a true bell curve is because you are dealing with a mold that has a finite fill point. I worked in the plastic injection molding business for almost 20 years and we saw this everyday. When the mold is closed and filled, the only thing that can cause heavier than max boolits is a blown mold, i.e., separation at the parting line. Other possibilities are slight inconsistencies in the alloy, adding ingots to a melt might change the weight over a session. Larry's chart is pretty much what I would expect to see - a nice tight distribution when the mold is filled to capacity.

Shanghai Jack
05-07-2022, 10:19 PM
Just to add to the discussion - for my schuetzen competition with plain base bullets

I cast in a single cavity mold nose pour mold with an indexing mark working on the assumption that no two cavities will be identical.

I melt, clean and flux in one pot and transfer to another that never sees anything but the cleanest alloy I can make. Cleanliness is next to godliness.

I use the largest amount of 24-1 alloy that the second pot can hold no matter how many bullets I am casting and do not throw sprues back in the pot or add alloy after I start.

I watch the temperature like a hawk. The large amount of melt tends to stabilize the temperatures. 200 168 grainers uses about a quarter of the pot.
Going the Pope and Mann route I keep the bullets in the order cast. For a hundred round match I'll cast about two hundred.

A quick visual inspection eliminates those with obvious external physical defects - e.g. rounded bases, ugly grease groove, dross inclusions, or anything else. I'll also discard any frosted bullets but I don't get a lot of those.

Depending on my mood, this usually eliminates 50 or so. They go into the box for scrap lead along with the sprues. I use this scrap for non critical casting like .45 caliber round noses and such stuff.

Then, with the bullets still in as cast order I weigh. Since my alloy is always the same I don't do the bell-curve thing - just discard obvious outliers which probably represent an internal dross inclusion, void, failure to completely close the mold, etc.
This usually, depending on my mood once again eliminates another 5 - 10.

Then I lube and shoot in order cast indexing the bullet to the bore. If its going to be a congenial shoot, I don't lube until I'm ready to seat the bullet into the gun. Nothing like fresh lube. I reserve the first and last 10 cast for foulers and sighters. If I don't use them when the match is over they go in the scrap.

I know its probably anal but I really enjoy casting what I consider to be the absolute best bullet I can. Its a long process but, for me, its worth it.

Don't even get me started on lubes. I'm still looking for the odd bottle of sperm whale oil.

If you were using plain base bullets I'd say that you had damage to the steering end (base) of the bullet. Perhaps the seating of the gas check is slightly askew or its separating at the muzzle or somewhere down range.

I wouldn't think that losing lube in a part of a grease groove would be significant enough to cause a 4 inch flier.

Most often when I see a uncalled flier that I can't blame on a bad bullet its something I've done to the gun like resting the forearm on a different spot on the rest causing a change in barrel harmonics or shooting too rapidly but its not usually 4 minutes of angle.

Bad Ass Wallace
05-08-2022, 01:41 AM
There is not just "one thing" that is the controlling factor in shooting good groups. Boolit weight is one but so to case preparation, neck turning, primer pocket deburring, trimming to length etc. I weigh all boolits into batches. No matter how close you inspect them some wlll weigh heavy and some light. In my 30.06 substituting Federal LP primers for LR primers annulled the occasional flyer.

My load of 31.5gns of 3031 showed just 16fps spread over the chronograph. Prior LR primers gave an xtreame spread of 82fps, giving vertical stringing.

https://i.imgur.com/SabiU6Dm.jpg