12-27-2017, 05:00 AM
I've been an advocate of AR-Comp and have shot a lot of it. 27.6 gr behind 123 gr bullets loaded to around 2.260". They have shot great in my Grendels. The chronograph 2490 to 2500 fps in my 18" LaRue.
My latest Labradar chronograph session has me scratching my head. I was checking velocities through my new build 20" Proof Research barreled upper. Velocities with factory AMAX ran 2491 fps. A load with 28 gr of TAC ran 2459 fps. These were about what I expected. Velocities with my AR-Comp loads ran about 80 - 100 fps higher than I expected at 2580 fps and I was seeing slight ejector swipes. I think I'm going to back it off a little to get the velocity to about 2500 fps.
My latest Labradar chronograph session has me scratching my head. I was checking velocities through my new build 20" Proof Research barreled upper. Velocities with factory AMAX ran 2491 fps. A load with 28 gr of TAC ran 2459 fps. These were about what I expected. Velocities with my AR-Comp loads ran about 80 - 100 fps higher than I expected at 2580 fps and I was seeing slight ejector swipes. I think I'm going to back it off a little to get the velocity to about 2500 fps.
Cliff
USN Ret., FPD Ret.
Dues Vult
USN Ret., FPD Ret.
Dues Vult

