I agree it's probably a bad thing to reload steel, but back when my department had Thompsons, there was so much surplus ammo available that we used to shoot trap with the Thompsons! Most of the ammo was RA-whatever, but a lot of it was steel, too. Being frugal, I decided to use the steel cases, if they were reloadable, as throwaway ammo. In other words, I decimated the jackrabbit population and never worried about reloading, or even picking up, the case a second time. It's hard to feel great about making a great shot when you're mourning the loss of good brass!
All this loading was done with steel dies, simply because carbide was not available. I just wiped the cases off (no tumblers, either) and loaded it with cast bullets. Never had any loading problems, didn't ruin my dies, hit a lot of bunnies, and never had any extractor problems. Now that I'm a little more flush, and have better guns, I probably wouldn't use them any more, but they filled a need then, and did it well.