CMMG 55BA492 AR-15 Firing Pin Stainless Steel

The CMMG 55BA492 firing pin is a drop-in replacement component designed for the AR-15 platform. Machined from stainless steel - reflected in the "SST" suffix in CMMG's part designation - this firing pin delivers the corrosion resistance and durability expected for high-round-count shooting, hard-use builds, and long-term field reliability.

Suitable for use with .223 Remington, 5.56x45mm NATO, and 300 Blackout chamberings, the 55BA492 fits standard AR-15 bolt assemblies used in semi-auto rifles and AR pistols. It serves as a direct replacement for worn, damaged, or lost factory firing pins during routine maintenance, bolt rebuilds, or complete parts swaps, restoring reliable primer strike performance to your bolt.

The pin is finished in a natural silver stainless tone and installs directly into the bolt without modification, making it a staple for armorers, gunsmiths, and home builders who need a dependable spare on the bench. As an OEM-pattern component from CMMG, a well-known AR-15 component manufacturer, the 55BA492 is built to drop into the bolt and keep your AR-15 running.