My thought is that you need to let us see it. Pictures sure would be nice since I am not sure what a M1-22 is.
As far as what brand of ammo goes, anything that you can find right now would be a good place to start. I have been using Remington Thunderbolt in all of my .22s, pretty cheap ammo but I have never had any problem with it.
I haven't fired one, but have examined. These appear to be very cool little rifles.
I know that Chiappa recommended CCI Mini Mags in the 1911/22 I bought (Which IMO was a POS that I got rid of).
Very interested in hearing how you like your rifle.
Thanks for the link Fatstrat. I also had a POS Chiappa 1911-22. I like the looks of this little carbine, if I had not known it was a .22 I could not tell by looking, I wonder if a carbine bayonet will fit it. I do hope they did a better job on this one than they did on the 1911.
I wondered about the bayonet too. The safety popped out, at my prodding, because it seemed to be loose. That spring and the mag release are inter-related and I wound up cobbling it back together. I took it apart, because I'm terribly curious, but am in no way as qualified as say, a, Henry Ford, all the stuff he took apart worked again upon reassembly, I'm told; not so with lil Johnny. If it shoots I'll be happy. If I could find any 22's round these parts, Davenport Ia. and environs, I'd be happy to try Remington, or anything else for that matter. But alas the shelves are all M/T! It's a dry well in these parts a the woods. I'm so glad I bought, what I bought, when I bought it, cause they ain't no mo!