The XP 100 is one that I have had a lot of interest in a number of years ago. I had JD Jones at SSK industries punch out the 7br to a 284 with the stock BBL. He has a way to do this with out leaving the shoulder ring from the 7br in the finished gun. Also he wont do this with out a break unless you have a really good stock. I don't have a break on mine and have a hand picked wood stock that has not broke yet. I will say that the recoil is "Brutal' on mine with out the break. How ever it is the most accurate XP that I own to date. Best of luck with yours.