Subsonic loads in the .223 are a pain in the dick even with a bolt gun. I'd not bother attempting them with an AR.
Blackout would be a better option in my opinion.
Travis
Why an issue with a bolt?
For the other "22lr suppressed is better" comments, I own two 22lr cans. And yes, for those on a tight budget and wanting a suppressor, a 22lr can is the cats meow.
