Faxon 9310 Nitride Bolt Carrier Group 5.56x45mm NATO

The Faxon 9310 Nitride Bolt Carrier Group is a replacement bolt carrier assembly for AR-15 rifles chambered in 5.56x45mm NATO and 223 Remington. It is built from 9310 steel, which the manufacturer rates as stronger than the C158 steel used in many standard bolts, and it receives a black nitride finish. Nitriding raises surface hardness, reduces friction and improves corrosion resistance compared with chrome or phosphate finishes.

The bolt undergoes full heat treatment, shot peening to MIL-SPEC and magnetic particle inspection to check for defects. Bolt lugs are chamfered 45 degrees, and the extractor is made from S7 tool steel with a QPQ salt bath nitride finish. The assembly includes the extractor spring, insert and o-ring.

• Platform: AR-15
• Calibers: 5.56x45mm NATO, 223 Remington
• Material: 9310 Steel
• Finish: Black Nitride
• Color: Black
• Extractor Material: S7 tool steel
• Inspection: Magnetic Particle Inspection (MPI)
• Included: Extractor spring, insert and o-ring