Originally Posted By: Daryl Hallquist
Rocketman, I understand the concept of working metal and making it "harder", but cannot understand how you might have a stronger spot in a barrel after a bulge repair. Afterall, the bulge seems to make the barrel wall thinner, so how does pounding , or shall we say, moving the stretched metal back into position make for a "stronger" spot. There was a fixed amount of metal in the bulge area before bulging, the same amount, but in a different set of dimensions, after bulging, and, unless mechanically removed during repair, there is the same amount after "shrinking" the bulge back into the original dimensions. If the same amount of metal is still present and the original dimensions have been restored, you should expect the barrel wall thickness to be as original and as the surrounding walls. However, the bulged metal has been through two plastic deformations (like bending a wire and then straightening it) which will have hardened the deformed metal relative to undeformed metal in the surrounding barrel walls. If that were actually the case, I am surprised that gun sellers don't brag about the stronger barrels they have because of bulge repairs. Your position is the intuitively obvious one and gun sellers would not generally care to try explaining the metalurgy involved. Would there be fatigue at the joint of the original and repaired barrels ? That would depend on the extent of the deformation. A small, gentle bulge/dent will go back into place fairly nicely. A dent with a crease in the bottom may be a different story. At the point of "how bad is unrepairable?" I'll defer to the experience of barrel makers. If a good barrel man declines to repair a dented or bulged barrel, I'll not be the one to argue whit him.