Hi Destry, My Jeffery 10 went through 3 1/2" magnum proofing last summer without a whimper.Original overbored barrels and 50 thou
barrel walls. The gun was tight on face when obtained and did not require any work other than a light polish of the bores before re-proof.Another dangerous damascus gun handles 1200 Bar proofing.
It is not my intent to shoot magnum factory loads in it,as I do most of my own reloading, but it is comforting to know that it could. 35+ years of shooting damascus with nitro for black, and all fingers intact.
Terry

Better to keep your mouth shut and be thought stupid,than open it and confirm.