James; no matter what you end up doing, you're still going to have a non-standard threaded tenon. Either a tilted thread or a considerably oversized thread. Obviously the turd cut the receiver thread tilted to mate with the barrel thread. To me that would be more acceptable for you to do than thinning the receiver ring at the thread root by cutting a true thread to a considerably larger diameter. From an engineering standpoint, a cylinder under internal pressure will split lengthwise at only half the pressure required to cause it to fail around its girth. Logically, the material lost by enlarging the thread diameter would be replaced by the corresponding increase in the tenon diameter, but my instinct is not to thin the receiver wall. Also, V form threads will exert a lot of radial force when made up hard, so the thicker the receiver wall, the better to resist circumferential stretching from the pitch faces pushing outward, and if it's a sort-of backwards buttress thread, it's going to exert more radial force than a correct 60 degree thread. On the other hand, if the mating pitch faces are on the more vertical side of the thread, that actually isn't bad.
Either way, I would match the thread form, chamber for a case no larger than a std magnum, make up at around 50 - 75 ft/lbs instead of 100 - 125 ft/lbs., and come up with a way to identify the non-standard thread by stamping or with an engraving pen, (maybe on the bottom of the barrel where a 'smith would see it before breaking it out. Then I would tie it down, use a long string, test fire it with several max pressure loads and check extraction and case expansion to be sure it is O.K.
On edit: added long string.
I think you can save it. Let us know what you decide, Tom
Texas State Rifle Association Life Member
NRA Endowment Life Member
A big fast bullet will beat a little fast bullet every time
Last edited by specweldtom; 01-28-2008 at 12:08 AM.