The Faxon 9310 5.56 Bolt (.125) – Nitride is a high-quality replacement bolt engineered for AR-15 platforms, designed to deliver reliable function and extended service life. Faxon constructs this bolt from 9310 tool steel, applying tight process control and enhanced finishing techniques to ensure dependable performance. All bolts undergo Magnetic Particle Inspection (MPI) to verify material integrity and confirm freedom from defects.
Salt bath nitride treatment hardens the surface, reduces friction, and provides superior corrosion resistance compared to standard phosphate finishes. The bolt lugs feature chamfering to promote consistent cycling under high-pressure loads and rapid action sequences. The extractor is fabricated from S7 tool steel, fully heat-treated and shot-peened for durability.
The salt bath nitride process simultaneously increases surface hardness and corrosion resistance while lowering friction—benefits that typically translate to smoother operation and easier maintenance. Faxon Firearms stands behind all products with a Lifetime Guarantee to the original purchaser covering defects in materials and workmanship.
