CMMG Bolt Assembly AR-15 5.56 NATO 9310 Steel Phosphate Black

The CMMG AR-15 Bolt Assembly is a drop-in replacement bolt for the AR-15 platform, chambered in 5.56x45mm NATO and fully compatible with .223 Remington. It is an ideal spare or service-rebuild component for any standard AR-15, manufactured to the same quality standard CMMG installs in their complete rifles and uppers.

The bolt body is machined from 9310 steel and finished in a corrosion-resistant phosphate coating (black) for long service life under hard use. The extractor is manufactured from 4140 steel with a matching phosphate finish. The assembly ships with the extractor, ejector, and gas rings pre-installed, so you can drop it straight into a compatible bolt carrier.

This is an authentic CMMG part (part number 55BA457), sold as a bolt assembly only - no bolt carrier group, barrel, or other components are included.