Just got it back from MCR with conversion. Barrel nut on the IBI 22" 1/12 barrel- thats the way they do it. You can adjust headspace that way. Now that it have the conversion , doesn't really help. Headspaced for Eley. Ships to your FFL with one mag and barrel nut tool. . $1900 shipped-I've got $2300 in it. He's not taking new orders, as a side note. Paypal friend or Venmo- don't have Zelle.