I've never made a gun, nor know the mechanics all that well, yet I have tried to look for answers but I haven't been able to find them. I am interested in seeing if there is a possibility of converting the Ruger PC 9 back and forth from the 10/22. For example I know that the glock 19 can swap uppers with the glock 22cal (I forgot the model #). Is it possible to do the same with the PC 9 and 10/22 which are on similar platforms? I am also interested in the possibility of making a Franken Gun with a double stacked 9mm, 22 combo with a longer 9mm barrel stacked on top. Most likely a 16" 22 barrel, under a, I am taking shot from the dark here, a 18-20" 9mm stacked, further back. Ideally suppressed barrels, but I don't know crap about them yet so I am being idealistic. I would use a simple blow back system for each. I know that a single shot is possible, but I am interested in simi-auto for both. If you could let me know, I'd appreciate it, thank you.