Some years ago, I bought a 7mm-08 barrel here on the forum and it had pop open issues. I tried it on four or five different frames with the same results. I smoked the latch shelf, etc. and it looked as though it had already been stoned down too much. I compared the lug and shelf to my .30-30 which locked up and shot fine on all the frames tried. I took both the .30-30 barrel and the 7-08 to a machinist/welder friend and asked if he could restore the lug to the same profile as the .30-30. He said he could, but asked if it could wait. He was very busy. I said sure and brought them both home.
Yesterday, a spare SB2 frame I bought from another member here arrived. A NEF NS prefix. I was down to only one each SB1 and SB2. Just for laughs, I dragged out the 7mm barrel and tried it on the frame. It locked up perfectly. No big deal, they all locked up. I decided to try it with some hot 140 gr. reloads.......guess what.....no pop opens
I suppose the moral of the story is keep extra frames around. In this case, it just took the right one to fix it.
Pete
