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CMMG makes a dedicated upper 22 LR barrel and an Arthur Ciener conversion style bolt assembly that can be assembled on a regular ar upper. I've got one of these but with an A1 style barrel I made from scratch and I've had zero issues with it. I shoot 45 gr subs suppressed mostly but it will cycle anything from CCI quiets to Sniper subsonic and stingers.https://cmmg.com/barrel-and-bolt-group-kit-16-1-m4-22lr
CMMG makes a dedicated upper 22 LR barrel and an Arthur Ciener conversion style bolt assembly that can be assembled on a regular ar upper. I've got one of these but with an A1 style barrel I made from scratch and I've had zero issues with it. I shoot 45 gr subs suppressed mostly but it will cycle anything from CCI quiets to Sniper subsonic and stingers.
https://cmmg.com/barrel-and-bolt-group-kit-16-1-m4-22lr