GeorgiaBoy,
If he opens the bolt up to a standard bolt face...it will no longer be a 223Rem. He will by necessity rebarrel and headspace.
You are correct and not correct in the same sentence. I had a .223 and changed the bolt face to a magnum. Then I had the same barrel rechambered to my .264 Win Mag case necked to .224. I called it .224MBOC.