I have welded LC Smith barrels. My barrels contained enough carbon that the weld heat affected zone hardened as it self quenched from the barrels being room temp. This weld was accomplished using low carbon steel rod, which I recommend for this repair. It was then annealed by torch. I think you could use a 4130 rod as well. It would need to be annealed as well. Close inspection for cracks should be made after welding and after filing the weld down. I would even go so far as to use a magnaflux or dye penetrant inspection.

And Keith's recommendations sound right on...copper backer, purge.

Last edited by Chuck H; 01/25/12 10:20 PM.