Wow. I can't say enough bad stuff about the P22. Even the folks that like 'em agree they are poorly made. There's a 100 page document you can find online that describes way to modify them so they will run better.
I was thinking about getting one to train with so I borrowed a buddy's. It was bad. Mis feeds, stovepipes, FT feed ,FT fire. Had a guy offer to sell me one a coupla weeks ago when I was looking.He wanted $350 I turned him down ( after testing out my friend's)and told him I thought they were junk . He said " I know, how about $200?" Turned him down at that price too.
I would get your son a ruger 22/45 not near as expensive and once the loaded chamber indicator is removed, it should function perfectly.
Can you find that document? I will start searching after I read that... I learned on the hi-point forums what problems they had and what other people were doing, and took my own approach. I had better tools than they did, being a machinist, so i could put a mirror finish on the feed ramps rather than just taking the paint off with a pencil eraser in a drill. Love the hi-point now.
As someone else said, a can is probably next. I've been looking at the Tac-65. I thought about making my own on a Form 1, but I can't beat the quality and price of the Tac-65. I wouldn't be saving much money by making one before it's all said and done, and I have to pay the $200 tax stamp anyways, I might as well get something nice and ready to bolt on. I don't have to deal with the headache of keeping everything centric +/- .001 (my own standards if i made something that had bullets going through it!) Besides, I'd have to get a thread adaptor from tacticalinc anyways.