Has any one here ever rechambered their 223 to 7mm tcu,would you just need the barrel bored to 284 or would you need the shoulder area changed in the chamber also.Other than being different is there any advantage to this rechamber?They seem to be popular in the 10 and14 " contenders ,how about the 22" handiWould this be a decent youth whitetail round, say 139 grain . :roll: