Weighing and sorting question

[Jeffery8mm]

Been casting ALOT of lyman429421 44 cal Keith boolits. I weighed 20 random boolits and came with these results. In my opinion, I aint gonna sort them as they are close enough to plink with. What do yall think about they results.???? Are these pretty close as far as cosistantcy??
Thanks

Jeff



http://www.easycalculation.com/statistics/standard-deviation.php


To Calculate Mean, Variance, Standard deviation :
Enter all the numbers separated by comma ",".
E.g: 13,23,12,44,55

252.4,253.5,251.3,252.3,250.8,252.5,251.9,254.0,25 4.7,254.9,254.8,252.2,255.9,255.2,252.3,255.9,255. 1,251.9,255.3,252.4



Results:
Total Numbers: 20
Mean (Average): 253.465
Standard deviation: 1.63459
Variance(Standard deviation): 2.67187
Population Standard deviation: 1.5932
Variance(Population Standard deviation): 2.53827

[trickg]

I'm curious to know what your mold is like - for instance, if you have a 2-cavity mold or a 4-cavity mold, do you know which cavity the bullets came from? In the little bit of reading I have done about casting (I have very little personal experience with it) it seems that each cavity usually weighs out slightly different for some reason or other, but that single cavity molds seem to be pretty consistent.

I think that it's more than good enough for plinking - I can't imagine that a standard deviation of roughly 1.5 gr (roughly .5 of a percentage point of the overall weight) is going to make that much of a difference.

Out of curiosity, has anyone ever done this sort of thing with commercially produced jacketed bullets to see what the variance of weight is between bullets? It's probably a bit tighter than hand cast bullets but there is undoubtedly still going to be some variance.

[GabbyM]

Yes I'd just shoot them.
For bullseye shooting you always weigh and sort bullets to hold a ten ring. Few out of the box pistols will hold a ten ring with any ammo.

Keeping the mold temperature and metal temp steady is the way to get consistent weight.
If you continually add spur metal back into the pot the metal temp will be up and down. I like to cast until the pot is low then take a break. 40lb pot helps as it takes 40 minutes to draw it down.

2 ½ grains is on the high side of deviation so I'm thinking you're adding spur and metal as you go. Since that's a most common practice. You could weight sort out a couple dozen and load them up to see if you can tell the difference in your revolver. My wild guess would be an inch at fifty yards. But that's a wild wild guess.

[beagle]

Those look all right. It's not worth weighing bullets for the .44s as internal voids will give those variables you posted.

I say it's not worth weighing as I have a M94 Winchester Legacy. When I firts got it, I scoped it and tested some loads for accuracy. Out of 5 groups in the first batch it produced several groups around 1" at 100 yards with the 429421 sized .431" and 16.0 grains of WC820 with a Winchester large pistol primer. Not a streaking, powerhouse load but it served my purpose.

This was with random selected air cooled WW alloy bullets.

Now, if you have loads of time, by all means weight them if you want to but IMO, it's not worth it with a .44 bullet. Now, .22 bullets are different. You can pick up 1/4" to 1/2" smaller groups if you do it./beagle

[trickg]

If I ever got to where I was shooting competitively, I would definitely sort bullets by weight, but for the shooting I do, which at the moment is 100% recreational, I'd load 'em and go. :)

[montana_charlie]

In my opinion, I aint gonna sort them as they are close enough to plink with. What do yall think about they results.???? Are these pretty close as far as cosistantcy??
Doesn't matter what we think...
Since you made them for plinking with a revolver, the only requirements are that they function safely, and don't lead the barrel.
When you decide to see how well that revolver can shoot...you will probably start to care about the 'quality' of your bullets.
CM

[Jeffery8mm]

Trick, this is a 2 cav mold. I water quench them so I cant speak for the individual cavities. Gabby, I am using a Lee 10 pounder, So I do add metal quite a bit. Am thinking of "warming" the ingots before adding them to the pot. Any suggestions on that?? Perhaps sitting an ingot on the side of the post may help??
Time does not really permit me to weight each one and I am only shooting bowling pins so I shall load them up and fire away. Even though they aren't weighed and sorted, I still consider them "quality" boolits. But that's just me.

Thanks
Jeff

[kooz]

I took all the 429421 rejects that I have acumulated after the last several lube sessions and loaded them over 7.5gr of Unique and took them to the range to see how well they would do @ 25yds rested. These were really in bad shape very big weight differences and partially filled out driving bands, they looked pathetic, however, one thing they did all have was a completely filled out base . Well, I never got a group over 2.5" and most ran under 2".

[454PB]

Jeff you can answer this yourself pretty easy. Weigh 50 boolits to within 1 grain, load them, then shoot them from a rest for groups. Next, do the same with 50 visually selected "perfect" boolits.

My conclusion after doing this many times was that weighing each boolit was a waste of time. As long as they pass a visual inspection, they are going to shoot. I don't keep "plinkers", it's just too easy to throw them in the reject bin and recast.

[AZ-Stew]

Your deviations are approximately +/- 0.5 (1/2) percent. That's not bad for cast. The factory swaged lead and jacketed bullets vary +/- a couple of tenths of a grain, but that in itself doesn't make them more accurate. They are essentially void-free and they have very uniform base corners. The latter has far more effect on accuracy than 1/2 percent weight variance.

If you want accurate cast boolits, cull out the ones that have rounded base corners. Even if they look uniformly rounded, they aren't, and they're surely different from any others in the batch with rounded bases. Use the rounded ones for plinkers.

Regards,

Stew

[Junior1942]

My conclusion after doing this many times was that weighing each boolit was a waste of time. As long as they pass a visual inspection, they are going to shoot.+1 on the waste of time. For me, a visual inspection-only works even for cast rifle bullets. Nowadays the only time I weigh bullets is to get the average weight of a new batch.

[mike in co]

i dont know what the rest of the makers do, but seirra's tolerance is plus or minus .3...atleast for rifle bullets.
definitly not used by reminton for thier bulk bullets( not even good enough for blasting).

mike in co

[Jeffery8mm]

Thanks guys!! I appreciate the feedback!!

Jeff

[GabbyM]

Trick, this is a 2 cav mold. I water quench them so I cant speak for the individual cavities. Gabby, I am using a Lee 10 pounder, So I do add metal quite a bit. Am thinking of "warming" the ingots before adding them to the pot. Any suggestions on that?? Perhaps sitting an ingot on the side of the post may help??
Time does not really permit me to weight each one and I am only shooting bowling pins so I shall load them up and fire away. Even though they aren't weighed and sorted, I still consider them "quality" boolits. But that's just me.

Thanks
Jeff

Preheating the ingots will speed things up for you. Resting them on the edge has worked for me in the past. Although if you bump one over in the pot it can splash out molten lead.

A hot plate with a second pot on it then ladle over molten lead into your casting pot also works. But of course you're accumulating more equipment and cost. Sometimes if you know what you'd like you'll find it laying around someplace cheep or free. I've a nifty little lead pot that looks like it was an insert in a restaurant steam table in a previous life.

The set up you have will work fine as it has for countless casters. In time you'll refine your set up and processes. Leaving rows of dead bowling pins in your wake.