A buddy of mine has half a dozen of them. They are fun to plink around with, but that is about it. If you bought the longer adapters, you might get something with some accuracy, but the short ones are about worthless, IMO
Most are ruined in short order. The also get pulled out/ruined by the extractor on anything other then a single shot or double barrel. Better off buying reloading gear or stash enough ammo.