JFKID:

not sure what kind of silver solder the manufacture manufacture used, but many really good gunsmiths I know are using a low temp silver, to attach sight bases and etc. that flows at 475 degrees f. and has 28,000 PSI tensile strength. Which means the repair can be made without effecting the bluing, but all the old solder will have to be removed first not knowing what it is. If the barrel is not bent any competent gunsmith should be able to make the repair. The solder is called "HI-FORCE 44" and is available from Brownell's

Bob