Marrakai,

Thanks for checking Nigel Brown's reference.

Actually the charges are even more unusual....

left barrel: "first charge
12 drams
shot 1 1/4oz"

right barrel: "second charge
6 1/2drams
shot 1 7/8"

Can't imagine how they stuffed all that in a 16b shell!
The gun is still tight and on face.
Guess those damascus barrels are fairly strong!

Over on the Shooting Sportsman BBS a Mr Baines has the info and just happens to be going by the Birmingham Proof House on 1/11. Will be interesting to see what he thinks.

Jeff