I seem to recall William Buchele suggesting a tapered shim or spacer. This was when swamped barrels were harder to get, and people were building lightweight longrifles with 13/16" straight barrels. I believe Mr. Buchele felt that widening the breech in this way would improve the geometry of the rifle stock in the breech and wrist areas. @Wyogoat (post #17) mentioned this, also. So, I have heard of this sort of thing, but I don't think I've actually seen one before.
That looks like a nice rifle, at a good price.
Notchy Bob
That looks like a nice rifle, at a good price.
Notchy Bob