there's the problems of a front sight getting in the way, particaurlarly one with a dovetail, like most .22 rifles. there's the problem of a slide covering the barrel, like with a PPK, dumbass. There's the problem of of removing the barrel from the receiver, huge PITA with quite a few .22's. There's the problem of arranging for a shoulder for the can to come up against.
For the OTHER dumbass, I've female threaded at least 100 .22 bores. If you'd like to LEARN something, dumbass, first you have to admit how IGNORANT you are, and a pussy like you just CAN'T do that.
Hey, dumbass, I managed to inside thread the 3/8" OD of the Jennings .22 barrel. How would you do THAT, dumbass? I used an M letter drill bit, and a 5/16x40 tap, dumbass.