Vickers Hardness Measurements of the M855 Cartridge Case Base

摘要

Vickers hardness measurements were taken in order to create an axial and radial map of the base of the M855 cartridge case base. The goal of this investigation was to evaluate the difference in the material properties between cartridge cases that exhibited a dropped primer and those that did not. Dropped primers are instances when during the ignition and combustion of the propellant, as well as the kinematic motion of the weapon, the primer becomes separated from the primary cartridge case body. The free primer will either be ejected from the weapon or may remain within the weapon, possibly producing a weapon stoppage. This research evaluates the hardness of the cartridge case brass near the primer pocket to see if material properties are a contributor to dropped primers.