Rim fire cartridge cases made of wrought aluminium alloy - saves stress relief annealing and weight compared with brass

摘要

A rim-fire cartride case for sporting guns or for bolt setting guns is made of a wrought aluminium alloy with Mg and/or Mn as the essential alloying components. Other elements such as Si, Fe, Cu, Cr and/or Zn can be present in amounts of =0.6 wt.%. This saves all stress relief annealing operations after deep drawing, compared with the conventional brass cases. The new cartridge cases are two-thirds lighter in weight than brass cases and have less tendency to stress-induced cracks.