BenL
John Galt Speaking.
In a previous thread, I posted that I picked up a 300 Blackout upper and said that I would post results when I had them.
I went to Hap Baker yesterday, and put 80 rounds down range to test the new upper. I shot 20 rounds, then started recording velocities for the upper. I was shooting factory Remington 220gr subsonic ammo.
The gun was set up with a 16" CMMG 300 AAC Blackout upper with 51T suppressor quick attach, Rock River National Match trigger, Magpul PRS stock, American Defense base and U.S. Optics 1.8-10X scope.
My question was one of accuracy: is this upper a 1 MoA upper? The answer is "probably". In the end, I think the limiting factor was the factory ammo.
After shooting and measuring 30 rounds, the average speed was 1062fps, with a standard deviation of 44.1fps and an extreme spread of 186fps (1010 and 1196.) At the end of the 80 rounds, I could look at the speed and call how far off the shot would be. If the rounds were consistent, I would get 100 yard groups like this (yes, I'm aware it's only a 3 shot group):
However, it was tough getting a few rounds that were (nearly) the same speed, so most groups looked something like this:
If you look close, you can see the two top holes look as if the bullet went in a little canted; like the bullet didn't quite stabilize.
I'd bet with hand loading, I could get consistent 1" groups, if I do my part.
I went to Hap Baker yesterday, and put 80 rounds down range to test the new upper. I shot 20 rounds, then started recording velocities for the upper. I was shooting factory Remington 220gr subsonic ammo.
The gun was set up with a 16" CMMG 300 AAC Blackout upper with 51T suppressor quick attach, Rock River National Match trigger, Magpul PRS stock, American Defense base and U.S. Optics 1.8-10X scope.
My question was one of accuracy: is this upper a 1 MoA upper? The answer is "probably". In the end, I think the limiting factor was the factory ammo.
After shooting and measuring 30 rounds, the average speed was 1062fps, with a standard deviation of 44.1fps and an extreme spread of 186fps (1010 and 1196.) At the end of the 80 rounds, I could look at the speed and call how far off the shot would be. If the rounds were consistent, I would get 100 yard groups like this (yes, I'm aware it's only a 3 shot group):
However, it was tough getting a few rounds that were (nearly) the same speed, so most groups looked something like this:
If you look close, you can see the two top holes look as if the bullet went in a little canted; like the bullet didn't quite stabilize.
I'd bet with hand loading, I could get consistent 1" groups, if I do my part.
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