I have a 17 and a 22, and I can tell you that barrels,slides,and lowerswill all interchange and work.However, I got a chance to talk to the Glock reps at the NRA convention in Kansas City this past summer,and they cautioned me not to do it. The main reason was noted in the previous reply from "Big Bad Wolf". So I don't trade parts anymore,but, in an emergancy situation,it can be done.