THE COLT SMG UPPER RECEIVER DIARIES

The best in the bolt provider groups. The best would be the common five.56mm bolt carrier group. Detect the bolt, cam pin along with the carrier important. On The underside may be the 9mm SMG bolt group.It can be a typical FSB and no I'd no difficulties sighting it in. I initially constructed it having a DPMS A2 upper receiver before receiving the