Faxon Firearms 5.56 Gunner Lightweight 9310 BCG Nitrided – AR-15

The Faxon Firearms 5.56 Gunner Lightweight 9310 BCG is a reduced-weight bolt carrier group designed for AR-15 rifles in 5.56 NATO and .223 Remington. This BCG uses strategic material removal to reduce reciprocating mass without compromising structural integrity, resulting in faster cycling, reduced felt recoil, and less stress on buffer components. Ideal for competition shooters and those building lightweight carbines where every ounce counts.

The bolt is machined from 9310 steel—a nickel-chromium-molybdenum alloy known for superior toughness and fatigue resistance compared to standard Carpenter 158 steel. The entire assembly is treated with a nitrided finish, which diffuses nitrogen into the steel surface to create a wear-resistant, corrosion-resistant layer that holds up under high round counts. The nitride finish also reduces friction and simplifies cleaning. This is a drop-in component for mil-spec AR-15 upper receivers; no gunsmithing required. Properly headspaced and MPI tested.

• Part Type: Bolt Carrier Group
• Compatible Firearms: AR-15 (5.56 NATO / .223 Remington)
• Bolt Material: 9310 Steel
• Carrier Material: 8620 Steel
• Finish: Nitrided
• Weight: Lightweight (Reduced Mass)
• Installation: Drop-In
• Includes: Bolt, Carrier, Cam Pin, Firing Pin, Retaining Pin