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Danth
03-16-2021, 01:01 PM
Didn't know where to post this, but here's my question. I know if you use military brass to form another case, you need to account for reduced volume of the military brass. The reduced volume produces higher pressure but does it produce higher velocity as well? In other words, can I reduce the amount of powder and maintain velocity using military brass?

Mk42gunner
03-16-2021, 08:43 PM
Maybe. Not all military brass has lower volume; and if you are converting to anther cartridge anyway, all bets are off.

In theory with everything else equal, higher pressure should give higher velocity. I think in small arms ammo it will be very difficult to tell.

Be safe,

Robert

M-Tecs
03-16-2021, 09:56 PM
Rule of thumb is 308 and 30/06 have less volume than commercial. With 5.56 that not true.

279725

I have no way to accurately check pressure but I do have a chronograph. When using GI cases in the 308 or 30/06 I load to the same velocity are as my commercial brass. This is accomplished with slightly lighter charges. Doing this case life is equal so pressures are not much different. These loads are used for longer range competition and loaded to the point that loose primer pockets become an issue at about 10 loadings.