As far as the SBR route
I have a bush hampster dissy barrel that I'm going to cut down to 11.5 just for this
I also have a virgin lower that will get to be a pistol for the time the paper is pending so I can run it until the form 1 is approved. Gotta mill off the lower part of a carbine buffer tube so there's no confusion or legal issues.
I shot it this weekend, I dont care what you read the triple X is impressive.
It sounded like shooting a 10/22 unsupressed. I even unscrewed the can and shot one without it. Holy crap, huge difference. Definitely louder to the shooter than the bystander, ejection port is more noise than anything else. I would love to try this on a bolt gun or single shot.
I plan to buy an adjustable gas tube so I can shut off gas flow and fire it as a straight pull bolt. Should be alot quieter.
Right now it's on a midlength though and I havent seen any adjustable tubes for middy's yet.
I've been considering selling off the P22. It's uber cool suppressed and 100% reliable with the can but I just cant hit anything with it. The Ruger 22/45 is a much more accurate platform. Personally I cant see shooting a .22lr without the suppressor anymore. Once you get one you'll see what I mean. It's hard to remember it's still just as powerful and not a bb gun or stapler just because it sounds like one.