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Old 11-30-2010, 10:37 AM
snipecatcher snipecatcher is offline
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Join Date: Jul 2009
Posts: 177
Quote:
Originally Posted by rsilvers View Post
It is looking like a 12.5 inch 300 AAC BLACKOUT matches the velocity of a 16 inch 300 Fireball. This is probably due to the extra freebore (like 5.56mm compared to 223 or 6.8 SPC-II compared to 6.8 SPC SAAMI).

I was noticing that I could extra grains of powder before signs of pressure in a load that others were using with 18 grains. Previous loads will need to be re-worked up if you have a real 300 AAC BLACKOUT chamber. And remember - don't shoot 300 AAC BLACKOUT ammo in a previous chamber as it will have additional pressure.
But aren't your recommended seating depths extremely short to function correctly in the AR15 mag? Seated to your recommended OAL, seems like there is a lot of powder space wasted.
-Dan
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