Wilson Combat Low Mass Bolt Carrier Assembly - 5.56 NATO, Polished Nickel Boron The Wilson Combat Low Mass Bolt Carrier Assembly for 5.56 NATO is a precision-engineered component built for shooters who demand performance, reliability, and speed. Machined from aerospace-grade 9310 tool steel and subjected to Magnetic Particle Inspection (MPI), this bolt carrier group delivers superior toughness and consistency shot after shot. The carrier body is constructed from 8620 hardened steel with forward assist cuts, and the gas key is properly staked using Grade 8 fasteners to eliminate the risk of gas leakage or failure under pressure. A polished nickel boron coating covers the entire assembly, providing exceptional lubricity for smoother cycling, easier cleaning, and long-term corrosion resistance. At just 9.08 oz., the low mass design is the ideal choice for sporting and competition AR-15 rifles, offering quicker lock-up times and reduced recoil impulse -- especially when paired with an adjustable gas block. This BCG is a true drop-in fit for any quality 5.56 case-head based AR platform, including .223/5.56 NATO, .300 Blackout, .204 Ruger, .300 HAMR, and 7.62x40 WT. Product Highlights Aerospace-Grade 9310 Tool Steel Bolt: Precision machined and MPI inspected for superior toughness, durability, and consistent performance. Low Mass Design: Weighing just 9.08 oz., this carrier reduces recoil impulse and speeds up lock-up time, making it ideal for competition and sporting applications. Polished Nickel Boron Coating: Delivers enhanced lubricity, smoother cycling, simple cleanup, and robust corrosion protection. Properly Staked Gas Key: Secured with Grade 8 fasteners to prevent gas leakage or failure under pressure, ensuring reliable cycling every time. Universal Drop-In Compatibility: Fits any quality 5.56 case-head based AR rifle, including .223/5.56 NATO, .300 Blackout, .204 Ruger, .300 HAMR, and 7.62x40 WT. Specs Brand: Wilson Combat Manufacturer Part Number (MPN): WILTRBCALMPNIB UPC: 810025500726 Caliber: .223 REM / 5.56 NATO Firearm Type: Rifle Rifle Type: AR-15 Part Type: Bolt Carrier Assembly Carrier Material: 8620 Hardened Steel Bolt Material: 9310 Aerospace-Grade Tool Steel Finish: Polished Nickel Boron Weight: 9.08 oz. Length: 11 in. Carrier Profile: Low Mass / Semi-Auto Gas Key Fasteners: Grade 8, Properly Staked Inspection: Magnetic Particle Inspection (MPI) Compatible Calibers: .223/5.56 NATO, .300 Blackout, .204 Ruger, .300 HAMR, 7.62x40 WT Disclaimer: We strive to provide accurate and up-to-date product descriptions, specifications, and images; however, errors or omissions may occasionally occur. We are not responsible for any inaccuracies or discrepancies in the content provided. If you notice anything incorrect or unclear, please contact us so we can correct it. When in doubt, we recommend verifying details directly with the product&';s manufacturer.