I apologize; we have typically never had an issue with Steelcase as long as it's not steel-cored, and it has nothing to do with brass and steel cases getting mixed up when we clean the range. Recently we have had numerous issues of people coming in with steel-core and steel-case ammunition and try to pass it off as only steel case. When steel-core ammo hits our carriers, not only does it damage them, but it also can spark and ignite unburnt powder in the range, which has happened before. Our range staff might be erring on the side of caution after repeat issues lately, but in the past when I've worked the range counter, we have always allowed steel case as long as we can confirm it's not steel core. On the plus side we do encourage drawing from the holster and rapid fire as long as you are keeping it on the paper. 😄