Cryptic Bolt Carrier Group BCG - Complete .308 WIN/7.62x51mm/6.5 Creedmoor Nickel Boron CC-0205. 308 WIN / 7.62x51mm / 6.5 Creedmoor) machined from Mil-Spec 8620 aircraft quality steel with shrouded firing pin and Mil-Spec chrome lined interior. BCG...