seems like this discussion is revolving around pistol ammo, this thread may eventually get moved. there is pretty much a new thread about either wolf or tula(same manufacturer, different box) started every week it seems, some of the forum hounds get tired of the discussion after a while but not everyone browses every forum all the time so sarcasm really isn't called for.
to answer, steel does not expand as much as brass when it gets hot so a larger space exists between the chamber walls and the casing after firing. on direct impingement and blowback systems this cases a large amount of unburnt gun powder to enter the chamber and gunk your gun up faster than brass cased ammo. if you clean often then you will likely notice no difference at all. also there is a large debate that steel casings can dig into feed lips, get bound up inside magazines and snap extractors with prolonged use. I've noticed that a lot of these reported cases revolve around cheaply made products so if you are going to be using it in a Kel Tec or Kahr then I would recommend against it but springfields, smiths, glocks, sigs, HKs, Rugers and just about any mid to top tier guns would work fine.
