AB Arms AR-15 Firing Pin, 5.56mm, Chrome-Plated Steel

The AB Arms Firing Pin (AB Arms part no. ABAMSFP) is a mil-spec-dimension replacement firing pin built for 5.56mm/.223 AR-15 bolt carrier groups. American Built Arms machines it from AISI 8740 steel, a high-strength alloy commonly used in bolt and firing pin components, then chrome plates it for added corrosion resistance and a smoother strike surface. Because it’s cut to mil-spec dimensions, it drops into a standard AR-15 bolt without any fitting. It’s a straightforward way to replace a worn, bent, or broken factory firing pin and get a bolt carrier group back into service.

Key Specifications

• Machined from AISI 8740 steel, a high-strength alloy used in bolt and firing pin components.
• Finished with chrome plating for corrosion resistance and a smoother strike surface.
• Cut to AR-15 mil-spec dimensions for drop-in fit with standard bolt carrier groups.
• Sized for 5.56mm/.223 AR-15 bolts.

Frequently Asked Questions

Will this fit any AR-15 bolt? It’s cut to mil-spec dimensions, so it fits standard 5.56mm/.223 AR-15 bolt carrier groups.

Why chrome plate a firing pin? The chrome plating adds corrosion resistance and helps the pin strike smoothly and consistently over repeated cycles.

Buy the AB Arms AR-15 Firing Pin

Replace a worn or damaged firing pin with this mil-spec part from American Built Arms Company in our AR-15 parts selection. Order it from our Lubbock, Texas gun shop for fast, direct shipping right to your door.