Once the bolt carrier moves ahead, the bolt rotates and locks the lugs before the supporting lug abutments. When the group moves rearward, the cam pin forces the bolt to rotate and unlock from the barrel extension. The two ProMags I utilized labored flawlessly, plus the factory Five-seveN mag https://cmmg-mk5747813.ourcodeblog.com/30945358/cmmg-mk57-can-be-fun-for-anyone