You will need a bolt head for a .223 and the different front baffle to control the bolt throw but not entirely necessary. You will need the .223 mag box and spring and follower and that is it. I would pick a pointy bullet to use and feeding should be fine once you pick the barrel you need along with a barrel nut wrench and receiver wrench all from Jim at Northlandshooterssupply, his number is 1-763-682-4296