Faxon Firearms AR-15 Bolt Features The Faxon Firearms AR-15 Bolt starts from 9310 tool steel rather than the more common 8620 steel found in many factory bolts giving it greater strength and fatigue resistance under repeated cycling. Faxon applies a full mil-spec heat treatment and shot peens the bolt to mil-spec standards both of which improve the part s resistance to stress cracking over a long service life. Every bolt then undergoes magnetic particle inspection a nondestructive test that confirms the steel is free of subsurface flaws before it ever reaches a rifle. The back of the locking lugs is chamfered 45 degrees a detail that improves reliability during the highest pressure handloads and in fast lightweight actions. A black salt bath nitride finish increases surface hardness while decreasing friction giving the bolt superior corrosion resistance compared to typical phosphate coated bolts. The extractor is machined from S7 tool steel and sprung using a dedicated spring O-ring and silicone insert all installed at the factory and ready to run. This combination of hardened steel a tuned extractor spring system and a durable nitride coating gives shooters a bolt built to handle sustained use in competition duty or high round count training. Chambered for 5.56 NATO and fitted for AR-15 platforms this Faxon Firearms bolt is for sale at GrabAGun for shooters seeking a dependable upgrade over standard-issue components. Faxon Firearms AR-15 Bolt Specifications Manufacturer: Faxon Firearms Model: AR-15 Bolt Type: Bolt Caliber: 5.56 NATO Compatible Hosts: AR-15 Material: 9310 Tool Steel Finish: Black Nitride Weight: 4 oz Available At: GrabAGun