This Black Nitride 7.62x39 Complete BCG comes with an enhanced firing pin and is ready to be dropped into your 762x39 AR build. The enhanced firing pin provides reliable primer ignition. Standard firing pins do not protrude far enough to reliably set off 762x39 primers. Our enhanced firing pins are made to replicate the firing pin protrusion of an AK47 and eliminate this issue. No need for heavier hammer springs for reliable ignition.