I'm no expert on these things. But I know after the Civil War a lot of military arms were reamed out to smoothbore and converted to shotguns. That's what those look like to me - muskets that had the stock cut off in front of the rear barrel band and and the barrel cut behind the bayonet lug, or the lug ground off. Supposedly, they were available at every hardware store/gun shot in the country for next to nothing. Are they rifled or smooth?