Dinny, I'd been wanting another 7x57 for years, 'cause I don't believe it takes these super magnums to slay the white-tail buck. Maybe I'm just old fashioned, but I do believe putting one bullet where it belongs beats blowing both shoulders off.
MSP, here goes, altho some may think I'm crazy. The breakthru was about the size of a hat pin, and the hole was threaded .210x27tpi. Used a #3 drill with the point ground off which just removed the old thread and squared off the bottom of the hole, then threaded it 28tpi. Then used a piece of .250 drill rod and threaded it 28tpi not cut to full depth, tinned with silver solder, screwed into the hole and soldered, then dressed off flush. I then used a 1" piece of shotgun barrel with a rib attachment on it sectioned long ways and silver soldered under the barrel over the original hole. I then drill & tap the old rib lug for the forend screw. Should be strong enough, considering that the original deal was a brass screw into the leaking hole. Goatwhiskers the Elder