Constructed with precision, the nickel boron Wilson Combat Bolt Carrier Assembly for 5.56 NATO ensures performance and reliability when you need it most. This lightweight low mass bolt carrier assembly has been precision machined from aerospace-grade 9310 tool steel, providing superior toughness and durability. It's even gone through Magnetic Particle Inspection (MPI) to ensure optimal performance. For added strength and reliability, the carrier is constructed from 8620 hardened steel with forward assist cuts, while the gas key is properly staked using grade 8 fasteners so there are no worries about gas leakage or failure under pressure. To top it off, this BCG features a corrosion-resistant nickel boron coating for increased lubricity and smoother cycling of your rifle.To experience optimal recoil control and lightning-fast follow-up shots, Low Mass bolt carrier groups are the ideal choice for sporting or competition rifles. These lightweight carriers offer a quicker lock up time t...