How good is good enough

[August]

I suspect this might be akin to asking what kind of gas milage you're getting, but here goes. What is an acceptable level of variance for booolit weight? If I'm using 520 grain boolits, how many fractions of a grain plus or minus is acceptable for good accuracy? I know, it depends on what is meant by 'good,' but please tell me what your goal is when sorting your booolits for best performance.

Thanks.

Dave

[Dale53]

I shot BPCR Sil for many years. I constantly competed and was competitive. My standard was +or- .6 for the bigger bullets. My schuetzen rifle's bullet standard is +or- .2. Less is better and more is worse.

Dale53

[montana_charlie]

If you can settle on a 'percentage' of variance which meets your needs, you will never have to change as bullets get heavier or lighter.

If 1 percent off of the target weight is acceptable, that equates to 1 grain for 100 grainers...and 5 grains for 500 grainers.

It's still 1 percent of difference.
CM

[Pawpaw]

I usually sort cast bullets by standard deviation. My last batch of bullets (180 grain, .30 cal) had a standard deviation of 0.9 grains.

For a more detailed explanation, go here (http://www.castbullet.com/shooting/standard.htm). It is really easy to do once you learn the process.

[45 2.1]

I believe a better method than asking what boolit weight variance is ok is to ask how to cast boolits that have very little variance in weight. That is a subject that sees little ink!

[wills]

Sort them into groups so all boolits in the group are within a half grain of the same weight. 520.0-4; 520.5-9 etc.

Dan Theodore wrote a good article called, if memory serves correctly Cast 100 Match Grade Bullets Per Hour.

[NVcurmudgeon]

I have better things to do with my time than weigh boolits. Most of my shooting is practice in offhand and kneeling positions, or rock busting at long unknown distances. Neither of these pursuits requires weighed boolits, IMO. The only times I weigh boolits are when preparing to go to the Nevada Cast bullet Shoot, or whne loading for a postal match. Boolits for these purposes weigh between 175-213 gr. Using my PACT electronic scale I separate castings into one grain lots. e.g. 200.0 to 200.9. This seems to eliminate flyers. The small lots at the ends of the bell curve are not considered for including in my match ammunition.

[Bucks Owin]

I have better things to do with my time than weigh boolits. Most of my shooting is practice in offhand and kneeling positions, or rock busting at long unknown distances. Neither of these pursuits requires weighed boolits, IMO. The only times I weigh boolits are when preparing to go to the Nevada Cast bullet Shoot, or whne loading for a postal match. Boolits for these purposes weigh between 175-213 gr. Using my PACT electronic scale I separate castings into one grain lots. e.g. 200.0 to 200.9. This seems to eliminate flyers. The small lots at the ends of the bell curve are not considered for including in my match ammunition.

This is getting "off the trail" a little, but I just wondered how you like that PACT scale and which of the two models is it? I'm thinking of adding one to my "stuff". The price is reasonable and I like the fact it's "Made in the USA"!

Dennis

[hiram]

If you have a 520g bullet, and allow for 1g group separation, such as 518.0-518.9, 519.0-519.9, 520.0-520.9, you are talking about less than .2% (two tenths of 1 perscent) variation. I don't know if you could see a difference at 300 yds with bullets gouped by 1g or .5g. I personally group my lee 500 3r by 1g lots.

[BruceB]

For my part, I share Curmudgeon's position, in having better things to do than weigh bullets.

Every once in a while, I do find a reason to go weigh some bullets, which I normally do NOT do. Every time, I find myself reinforced in the feeling that it's just not necessary. I did a weighing session earlier this week in response to a thread here, and found (yet again) that the weight variations are so small as to be virtually meaningless (i.e.: about a one-grain EXTREME SPREAD on 500-grain bullets, or 1/5 of 1%).

There's enough history behind me now, in these occasional weighings of groups of my bullets, for me to have peace of mind about the minimal as-cast weight variations. Those variations are insignificant for the shooting I do. Visual inspection will continue to satisfy my criteria.

I also use the PACT scale, and it's a fine device. Mine is the original model, and I don't recall its designation just now. I'd hate to go back to the balance-beam, although I do keep an Ohaus 10-10 handy "just in case".

[NVcurmudgeon]

Bucks, my PACT appears to have no model number. The accompanying literature calls it a "digital precision powder measure." It must be old enough to buy a drink by now, and I have had zero trouble with it. That may be because I kept the foam packing material that came with it and fitted it into a cardboard box. I use it to weigh boolits only, preferring to use the old RCBS balance beam scale for powder. Speaking of RCBS, their digital scale appears to be a green clone of my PACT.