Builder,
The base wad from one shell is left in the barrel, when a subsequent shell is chambered and fired the damage is done.
It happened to me with reloaded AA hull, shortly after they changed the design. The gun is a 1927 Parker VHE. The barrel bulged slightly about 2-3" in front of the forcing cone. It was a concentric bulge and was just enough to break the solder joint on the bottom rib and loosen the barrel lug. I did not realize it right away and completed the round before I realized what had happened.....though it's hard to see the bulge you can feel it.
I wonder at times if it is repairable....It's a great gun and one day (when I have the $)I'll send it to one of the good barrel guys to get a definative answer.
Jeff
