Andrew Wiggin
New member
M855A1 "green" enhanced performance round fired from 14.5" barrel AR into calibrated 10% gelatin.
BB: 584.2 fps, 3.3"
Impact velocity: 3,013 fps
Penetration: 19.9"
Retained weight: 24.3 gr
Neck: 0.5"
TSC: 3.5" x 7"
The copper slug from the base of the projectile is the part that was recovered at 19.9" and weighed 24.3gr and measured 0.187" across the middle and 0.409" long.
The steel penetrator tip was found lying on the tarp and weighed 18.9 gr and measured 0.168" across the middle and 0.564" long.
The copper jacket fragmented completely.
Link to video of test
The performance in tissue was far better than I suspected, though not as good as most heavy OTMs like 77gr SMK. Still, those bullets wouldn't penetrate hard obstacles nearly as well as M855A1. Supposedly the pressure is lower now and the velocity of the round I tested is consistent with that, but it's still ridiculously fast.