Steel ammunition cases are made from soft, mild steel, not the hardened steel you find in weapons manufacturing. I've never seen or heard of any studies showing that steel-cased ammunition causes any significant wear beyond brass-cased ammo. Steel cases have been widely used by the US, Germanyicon, China, and the whole Sovieticon Bloc for many years. Can someone point to any information that shows any accelerated wear with steel-cased ammo???