Nice English hammer gun. Out of proof?

[edgarspencer]

Was this gun a 16 bore? How does someone hone .050" and expect there to be any wall left?

[Drew Hause]

Edgar: the 12 over C in the diamond was marked at the time of the original proof. 15/1 however would be considered a 14 bore.

The Proof House once thought a mistake was made, but on further examination found that there was not, nor has there ever been

[edgarspencer]

Thank you, Dr Drew. I missed the sideways 12, but never figured to look for a 12, when .719 is so much smaller.