The long one could also be a barrel from the "revival" period, where it was not uncommon to buttweld two old barrel together to get a longer barrel, sight radius, etc.
Charlie Bowers is very much alive last time I saw him. He makes the benchmark (censored) action that many chunk shooters use. I can probably find you contact info if you can't find it otherwise.
Looking forward to seeing more pictures. I would love to see the banned ones also, as they sound like top flight chunk guns, even with those "short" barrels, but alas, it cannot be
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