I think it is necessary to thoroughly examine barrels completely with a wall thickness gauge and if at all possible an endoscope. Ballistix's Clarke is a fine example of how things can go wrong. That incident could have had very serious repercussions.
We also went through a phase when the gunmakers were obsessed with producing light guns, and it was common practice to produce lightweight barrels, those barrels could still be out there one hundred years later plus a hone or two to remove pitting. Caveat Emptor. Buyer Beware.
