Aero Precision AR-15 5.56 PRO Bolt Carrier Group

The Aero Precision® AR-15 5.56 PRO Bolt Carrier Group is a professional-grade BCG upgrade, compatible with most Mil-Spec AR-15 rifles and carbines. Built from the ground up to meet the demands of the most extreme conditions, this complete BCG boasts a precision-machined 9310 steel bolt, finished with a proprietary flash nitride process to withstand extreme temperatures and pressures. The cam pin channel is counter-bored, eliminating the need for swaging, and the 4140 steel cam pin features an engraved indexing mark on one side of the pin face for consistent installation and reduced wear for improved service life. The enhanced 4140 steel extractor and S7 tool steel ejector ensure smooth and consistent operation, and the precision-ground and nitride-finished 8640 steel firing pin reduces the risk of light primer strikes for enhanced reliability and consistency. The hardened 4140 steel gas key is staked and torqued to military specifications with grade 8 hex fasteners, and the PRO carrier utilizes an M16 cut with precision-ground interior geometries to ensure optimal gas efficiency. What’s more, each component of the PRO 5.56 Bolt Carrier Group was deliberately chosen to increase the reliable service life of the bolt carrier group.