Accession Number:



Redesign of Copper Cylinder Used for M4, M16, and M249 Firing Pin Indent

Descriptive Note:

Technical Report,01 Feb 2013,30 Nov 2016

Corporate Author:

ARDEC, WSEC, RDAR-WSW-F Picatinny Arsenal United States

Report Date:


Pagination or Media Count:



A series of design experiments was conducted to update the U.S. Government copper crusher drawing for 5.56-mm weapon firing pin indent testing to current material standards with appropriate requirements that result in a manufacturable, consistent, and reliable crusher for firing pin indent testing. Three characteristics were determined to best define the cylinder, and were applicable to the final drawing revision. A clear definition of the production material was needed, as the state of the material controls the initial mechanical state of the product. The dimensional limits of the part are of second concern because without these constraints, the item cannot function as intended. For this case, the cylinders length, diameter, and surface-end perpendicularity was constrained in order to allow for proper fit and function during gaging use the establishment of compression testing at 45,000 psi by Frankford Arsenal, Philadelphia, PA, remains the ideal test for evaluating the cylinders mechanical properties.

Subject Categories:

  • Ammunition and Explosives

Distribution Statement: