sleev-les
Prestige Worldwide
A machinist/gunsmith can determine very easily if you brake is barrel metal or if it is attached. The easiest way is to simply look for the seam INSIDE the brake where the crown of the barrel sits. If none exists and the counterbore meeting the crown was obviously recess cut the "brake" is actually barrel metal. This is uncommon for several reasons, not the least of which is that a consistent crown is much harder to obtain. Factory rifles, well, that doesn't really concern Remington. In either case it is almost always easier (and thus cheaper) to cut it off and start fresh. I have run into this with the Savage "on/off" brakes and a couple of remingtons for friends of mine. They are invariably installed (if threaded on at all) with a ten foot wrench operated by Paul Bunyan after the evil Loctite Leprechaun spreads his juice all over the parts. Chuck the thing up, run a parting tool into the barrel, cut fresh barrel, then indicate in on bore, reface, thread if desired, and recrown.
I forgot to note that when you select your stock/chassis preference to budget in for bottom metal, inletting, and bedding. The XLR is a pretty tight fit on the rifles I have set them up on but for a truly perfect fit (particularly in a heavy recoil round such as you have) skim bedding may be desired. The chassis is the "bolt in" solution. A Manners stock will require final fitting, bottom metal installation, and a good epoxy bedding job.
It looks like the brake may actually be a separate piece. In certain light or shining a flashlight on the end of the barrel, you can actually see a very slight difference in color where the brake would stop and barrel would start. The inside also looks like there are 2 different widths with the brake being wider and the barrel being the correct round diameter. It's hard to completely tell since I was trying to use my phone for getting a picture down the barrel as I wasn't about to actually look down the barrel..