Experts on Guns and Shooting George Teasdale Teasdale-Buckell 1900
http://books.google.com/books?id=4xRmHkr7Lp8C&pg=PA373&dq
On the subject of steel v. Damascus, Mr Stephen Grant is very clear, and much prefers Damascus for hard working guns. He related an anecdote of one of his patrons, whose keeper stupidly put a 12-bore cartridge into his masters gun without knowing that he had previously inserted a 20-case, which had stuffed up the barrel. Fortunately, no burst occurred, but a big bulge, which, however, Mr Grant hammered down, and the gun is now as good as ever. shocked


1902 16g No. 0 L.C. Smith. Chambers extended to 2 7/8" with wall thickness at the end of the chamber of .096"



Looks pretty thin on radiography



But the MWT at the bulge was .102. Bore in bulge was .680; 3 1/2" .660" with WT .114"


Sad 12g Smith 4E with nice Chain Damascus with two bulges



The biggest bulge was at 4 1/2" with bore at 3 1/2" .735" and at the bulge .758".
Wall thickness at 3 1/2" was .118, 4" .092", in the bulge at 4 1/2" .078", and 5" .073".
4 1/2" non-bulged barrel was .090" and 5" .080"







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