These things can be tricky from a legal standpoint, but traditionally IF it has
rifling in the barrel then it isn't a technically a shotgun, and it might
chamber and fire .410 shotgun shells, but they can call it a .45Colt and get by
with it. For that matter T/C made several different versions with 10" barrels,
and now Taurus makes several different short barrel revolvers that chamber .410
shells in addition to .45Colt. If they ever make one without rifling then BATF
would be on their case.
I saw rumors of a 28 gauge revolver at the SHOT show, but I think BATF ruled
that it was a "destructive device".
> As far as I remember...
> The Thompson Encore 410/.45 Colt has a 15" barrrel and is legal *except* in