The highest of your bolt provider teams. The highest could be the regular 5.56mm bolt carrier team. See the bolt, cam pin as well as carrier important. On The underside is the 9mm SMG bolt group. As you would probably anticipate, it options an ejection port especially produced for pistol https://colt105upper07306.prublogger.com/26347792/the-colt-smg-upper-receiver-diaries