I'm looking for someone who can work on the Browning BLR. Trying to find a gunsmith to do a caliber conversion/rebarrel and cannot find anyone who will. I sure have heard a few people talking about the ones they have seen, but no one first hand, who can direct me to a gunsmith who can do it. I have found one guy who will do a trigger job for $120, but nothing else (I heard his work is very good). A Mr. Martin Potts, who posted here back a few years ago has a custom one, cut I can't get ahold of him. Can anyone lead me in the right direction. Thanks for the help.

Well, I've found someone. Actually two guys, but one doesn't even want to try it in .458WinMag, let alone the 458AR. He says it will just kick too hard, and no way he would do it on the take-down aluminum receiver. The other guy, a friend of mine now, said sure, just have to make sure it head-spaces right and fit the forearm. The secret was that the barrel extension and barrel really are two seperate pieces and you just have to "Time" the chambering job right. Opens a lot of doors to what can be done with a BLR.

What do you thing of the project? Any thoughts or sugestions?

The .458 has a very narrow range of application.
If you have never fired one you might try it first . I would be more inclined to build something in a cartridge that is not available ready made. In addition the cylindrical .458 might not feed well in that rifle. Why not something a little more useful? Maybe a .416 Taylor or a .375/338 or even a .358 Norma.