If I understand you ,you're talking about reboring and rechambering 7mmx57 barrelels to .30X57s and 8mmX57s to .338X57s. I ran into some difficulty. When I proposed a business proposition to a fellow who does reboring, he let me know there was a difficulty factor in reboring the 8X57s and he really didn't want to fool around with it. He wasn't explicite but left me with the feeling that the barrels don't rebore that easily.I was willing to invest in two to five hundred barrels in .338 after approving the quality of the reboring.Didn't fly. roger