The Faxon Superfinished .458 SOCOM / .450 Bushmaster Bolt Carrier Group (Nitride) is built for shooters running big-bore AR-15 platforms who want smooth cycling, dependable extraction, and long-term durability. Seeing “MIL-SPEC” as the starting point, Faxon upgrades the details that matter—materials, inspection, and surface finishing—to meet the demands of hard-use rifles.

This BCG features a 9310 tool steel bolt that is fully MPI tested, heat treated, and shot peened. The assembly receives a salt bath nitride treatment to increase surface hardness, reduce resistance, and provide superior corrosion resistance compared to typical chrome or phosphate finishes. Bolt lugs are chamfered to promote reliable cycling under high-pressure loads and fast action speeds.

Faxon Bolt Carrier Groups are Superfinished to reduce friction, increase smoothness of operation, and reduce fouling. The carrier is M16 pattern (full-auto compatible) and maintains the trip for full-auto fire control groups and many modern trigger systems. Gas keys use grade 8 fasteners and are fully staked for long-term reliability.

Specifications

• 9310 Tool Steel Bolt
• Full MIL-SPEC Heat Treatment
• Shot Peened to MIL-SPEC
• Magnetic Particle Inspection (MPI)
• Back of Lugs Chamfered for Reliability
• Spring, Insert, & “Crane” O-Ring Installed
• Salt Bath Nitrided Bolt & Carrier
• S7 Extractor
• Superfinished Carrier Body
• Full Auto Compatible (M16 Pattern)
• Forward Assist Serrations