Makes good sense what you said earlier about cleaning ammo that came off a belt or stored with cosmoline. As far as steel cased ammo, it is cheaper and for the most part, works well with minimal problems. The biggest problem with a steel casing is that when the powder ignites and creates all the pressure, the casing will expand a bit initially and as the pressure leaves the barrel, the casing contracts back to normal. Steel doesnt flex as well as brass, so sometimes the casing might swell and not return to size and results in a jam. I used steel ammo and didnt really care for it, especially when reloading and crimping. I was taught that thousands of rounds would need to be fired in order to see excessive wear in the chamber, but I never shot that much of it to know first hand. I guess I'd use it for practice, but probably not for regular use. There are also aluminium casings, but they are a one shot use and not to be reloaded. I reloaded some with wad cutters (less force to crimp) and a light charge and some of them still split.