Gizamo, I just came across your 7/23/10 "Octagon, to 16 Flats, to Wedding Band, then Round...." post. What a nice gun. And, great quality photos, too. Would it be too much to ask for some pictures of the lock area on both sides? Looks like it has a patent breech. Is it hooked or solid? I'd also like to see some under rib detail at the muzzle and a little more forward of the entry pipe than the photo you posted shows. Also, is the nose cap poured or a folded sheet?
I've got a shotgun that I was preparing to use as a subject for a build, but your's has me reconsidering. Mine's a back action with a patent breech, and an under rib too, but that's about where the similarities end. Yours is far more elegant.
Jack