[eflatminor]

Anyone tested the uniformity in weight between Winchester, Remington and Starline brass? Wondering which has the least variance.

[cdrt]

Any particular cartridge; rifle or pistol?

[ReloaderFred]

There are other variables besides weight to consider, such as wall thickness, wall uniformity, web thickness, rim measurements, etc. If you're talking about pistol brass, I don't think it matters that much, unless you're a dedicated 50 yard bullseye shooter, or possibly a silhouette shooter.

Hope this helps.

Fred

[eflatminor]

I am hoping to determine weight variances for .45 pistol brass. I'm a bullseye shooter. My plan is to weigh brass and group them into similar weights until I have 300 or so of one particular weight. These I will use only for serious matches. Before I start the tedious process of weighing out all that new brass, I wondered if either Win, Rem or Starline (reasonably affordable new .45 brass providers) has a reputation for greater weight consistency (i.e., less variance). If I knew before hand, it might quicken the process. I'm sure I'll have to go through thousands of pieces of brass to find 300 of the same weight.

I'm planning to do this because I know the advantage of using similar weight rounds with my rimfire Bullseye gun. My groups are much tighter when I use rounds of the same weight, so I always weigh and separate .22s designated for Bullseye. I even went so far to determine which particular .22 weight fired the tightest groups in my gun...those are saved for bigger matches. And if that weren't anal enough, I even measure rim thickness and further divide up rounds in each weight class! It's worth it for extra tight groupings with my .22 and I want to build a similar process for my .45 by starting with brass of the same weight.

Thanks

[Bad Flynch]

Spend your time dry firing; it will pay more dividends than will futzing with the brass. Just make sure that your brass for your money match is all one brand and lot.

[eflatminor]

Due respect Bad F but I think it's worth it to sort by weight. I also spend lots of time dry firing and I agree, that's most important but I'm looking for every advantage, mental or otherwise, to help improve my scores. Weighing .22 ammo makes a HUGE difference, of that I'm sure. Therefore, I have no reason to think otherwise as I seek to perfect my .45 loads for Bullseye.

[ReloaderFred]

You may want to look at Top Brass .45 or .45 +P from http://scharch.com/. It's some of the most uniform brass I've ever reloaded.

Hope this helps.

Fred

[eflatminor]

Thanks for the link Fred - I hadn't heard of Top Brass. Their claim of consistency is encouraging.

Do you know the difference between regular 45 ACP and +P? Starline also sells +P brass. What distinguishes the two? I would guess that the +P has thicker walls to withstand hotter loads???

Thanks

[Werewolf]

Weighing .22 ammo makes a HUGE difference, of that I'm sure. Therefore, I have no reason to think otherwise as I seek to perfect my .45 loads for Bullseye.With brass the weight is a function of length, diameter, wall thickness etc. Having 300 cases that all weigh the same in no way guarantees that each will be the same length, diameter and have the same wall thickness.

Why does that matter?

Take two cases of equal weight. One has a thicker wall and is a bit shorter than the other. The thicker wall makes it weigh the same as the other and makes up for the shortness. Result - even if you load both with equal volumes of powder - the shorter case with thicker wall has less volume and you get more pressure than in the other case assuming same OAL.

In rifle paying attention to brass weight and dimensions makes a difference - if you're shooting benchrest. In .45 ACP it just plain doesn't.

In .45ACP the critical parameters are OAL and how consistently you drop the powder. Pistols - all else being equal - just plain aren't accurate enough even if every round was 100% identical for the weighing of brass to make any difference at all. At 25 yards a top of the line 45 from a ransom rest might be capable of 1" groups, maybe a bit less. The kind of accuracy improvement gained by weighing and measuring brass might - with a rifle - account for .1" at 100yards. Bullseye???? Handheld - you've got way more slop in your group from the human factor (unless you're as steady as a ransom rest) than you'll ever get back by trying benchrest rifle cartridge loading techniques on a pistol cartridge.

Don't waste your time weighing .45ACP brass. Spend it assuring a consistent charge and OAL.

[Walkalong]

When you are living in the world of losing by a teenie tiny margin all things matter. I know where you are coming from eflatminor. It sucks to lose out over .0001 in an agg for a whole match, but I have done it. Did my brass make the difference? Maybe. Maybe it was that one bad shot between the ears too, but I still wanted my brass as close to the same as I could get them.

[Bullet]

You could also measure the volumes of your same weight cases and then weigh your primers too. Once your cartridges are all loaded you could weigh them again, then jump up and down 3 times close your eyes and repeat the secret chant. Oh and wear the same socks that you wore when you shot your best group. But if you do all this you better come in first.
I agree with Bad Flynch and Werewolf.

[eflatminor]

Your points are certainly valid Werewolf but I'm the kind of guy that enjoys seeking perfection, theoretical or otherwise. I absolutely ensure consistent charges with match ammo; same for OAL...and you're right, that's most important. I'm speculating that brass of similar weight are more likely to have similar internal dimensions. I would think that would help to control the explosion in a consistent manner...and hopefully, tighter groups.

Now if I was REALLY obsessive, I could measure the volume of each cartridge and group them that way...

I expect I'll just try a brand. Scharch at least advertises a commitment to consistency in OAL. I may try them if they get stock anytime soom (no .45ACP available now). Will report back for those that care.

[jeepmor]

Now if I was REALLY obsessive, I could measure the volume of each cartridge and group them that way...


I think this would be more productive for what you are trying to acheive. A consistent combustion chamber volume is more important than how much your brass weighs don't you think. I say this because a consistent weight means you have the same mass of brass, but does not directly correlate to the same internal dimensions as previously discussed. It should be close, all things being equal, but since your going for uber accuracy, I think time measuring volumes instead of the weight of each casing would provide more accuracy benefit.

If you're going through all this trouble, are you deburring all your flash holes too? Only have to do this once. I think this could be a bigger factor is squeezing out every micron of accuracy because it will make your ignition process (flame front propogation) more consistent.

good luck,

jeepmor

[eflatminor]

Jeepmore, how would you go about measuring internal volume? The only way I can think of is to plug the primer hole and fill up each cartridge with water, right to the rim, then weigh the water each piece of brass holds or perhaps pour the water into some kind of laboratory measuring cup??? I can't think how else to do it.

I have not deburred flash holes, though I do clean primer pockets for my current match brass. I'll give it a try, thanks.

[GunTech]

I've found Winchester to be about the best, but I still weigh. Lapua is more consistent, but even after weigh and sort, Winchester is cheaper.

[Walkalong]

Oh and wear the same socks that you wore when you shot your best group. But if you do all this you better come in first.
I would if I thought it would help me shoot another small group. Don't even get me started on my baseball superstitions. :D

[GunTech]

eflatmino,

You can weigh water filled brass. It about 1 CC per gram for deionized water, or if you're really a nit picker, you can calculate volume based on density at temperature. Just make sure you use the same meniscus.

http://www.thermexcel.com/english/tables/eau_atm.htm

[Bullet]

GunTech
I've found Winchester to be about the best, but I still weigh. Lapua is more consistent, but even after weigh and sort, Winchester is cheaper.

Where do you get 45 ACP Lapua brass?