Roy, those are good thoughts. I just cannot think that Mossy's gun has been altered. Do you know, in that time , if they used the bore designations of even numbers ? Later we see 13/1 etc for designations, sort of narrowing the diameters related to proof. By the way, I have seen a two barrel set, British hammer gun, with one set with 10 Chamber and 12 bore. I guess the maker would try lots of things in those days.

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