Surprised me, just figured it was on a 1 frame, but measures exactly 1 inch between pins.
Bores are still rough--but better. Used a wire bore brush, then wrapped a 20 ga brush with a scotchbrite piece soaked in Hoppes 9, and put cleaning rod in a drill. May do a little more
today. Just snapped barrels onto the frame, and they are way off face.

Off face

Looks like someone ground off the breeches on a wheel or a stone. Try those barrels on another 0 frame hammer gun to see where the metal is missing or worn.

it does looks like the breech end of the barrels have a rounded edge especially on the top - badly cleaned up?

how worn is the hook? and the hinge pin. I am just guessing that one or both have abnormal wear

i guess you could measure the depth of the extractor and compare it to another 16. does the rim cut look normal? if the back of the barrels were actually ground down - the extractor would have to be as well- i just doubt that was done

I have another very nice Quality O, O frame 16. The barrels will snap right on it but look the same, way off face--can this be fixed?

This is the old barrels on the other 16 gauge frame. Sure does swing nicely.

just about anything can be fixed, just takes time and money

that's a lot of gap - but off face issues are not the end of the world, most can be fixed by the right person

if good barrels fit the same. i would take a good hard look at the hinge pin, or better yet, have Brian look at it at Haussmans. he had some oversized replacements made

Very cool gun but it looking like a money pit to me. Is it me or does it appear to have a bulged chamber area.

No chamber bulge, Craig

I think the burlap strands are deceiving the eye, but I could be wrong.
There are some pits, that money just needs to be thrown into. I think this is one of them.