Alex Pro Firearms Bolt Carrier Group, Blue Steel

Alex Pro Firearms (APF) is excited to unveil our Bolt Carrier Groups (BCGs) featuring SP4, a cutting-edge hybrid DLC (Diamond-Like Carbon) coating developed over a year of rigorous testing. SP4 is engineered to combine exceptional hardness, rated at 2500-3500 HV, with ductility, ensuring toughness without the brittleness typically seen in common PVD/DLC thin film coatings. This advanced coating significantly reduces friction and enhances wear resistance for metal components, resulting in a longer lifespan and requiring minimal maintenance often needing little to no lubrication. SP4 has proven its durability in extreme conditions, successfully tested at -44 deg F in the Alaskan mountains and in both Iraq and Afghanistan without lubrication. This characteristic is a crucial advantage in both desert environments and extreme cold. Having passed the ASTM 85 (Annex 1) Salt Fog test, SP4 provides superior hardness and the lowest friction coefficient while maintaining the flexibility to "move" with the metal it protects. Each BCG comes with a hand-polished bolt carrier featuring a chrome-lined bore and a staked gas key, as well as a bolt equipped with gas rings, a firing pin, cam pin and firing pin retaining pin. Experience the unparalleled performance and reliability of APF's SP4-coated BCGs, designed for shooters who demand the best in any environment.