It wasn't as difficult as I thought it would be, watched a 2 minute video on youtube, bought the 222 Remington Finish Reamer, go gauge, no-go gauge, and a 3/8" driver extension, a few turns at a time and constant rechecking with the go gauge, and make sure the bolt doesn't fully close on the no-go gauge and I was good to go. I bought this Savage 340 used and the bolt wouldn't close very easily on a sized cartridge. And since the local gunsmith blew me off I decided to do it myself. And saved money!