Firing Pin for AR-15 / M16 Rifle

Our Swiss machining capabilities at Gent Machine are an ideal match for the production of precision components with a high length to diameter ratio. The part shown here is a firing pin that is used on the AR-15 and M16 rifles. The pin is machined from 8640 alloy steel and measures 3.375 in length with a 0.375 in diameter. Typically parts with long lengths and relatively small diameters are difficult to machine while holding precision tolerances using traditional lathes. Because the part is supported at its end, the level of distortion increases with the distance between the cutting surface and the end of the part.However, in Swiss machining, the workpiece is supported by a guide bushing that is located very close to the cutting tool, allowing us to hold very tight tolerances. Because it is such a critical moving component, the firing pin had to meet precision tolerances as tight as ±0.0005 in. In addition to machining, the firing pins required grinding and heat treating processes to meet the strength and finish requirements outlined in the customer specifications. We produced a total of 50,000 firing pins for this project with a turnaround time of 12 weeks. For additional information about this precision Swiss machining project, see the table below, or contact us directly.