An old boy i know has a converted original, shortened forestock & smoothbored barrel. He had had it since he was a kid, He had never used it but i found it was still loaded with a caked old charge of blackpowder & shot.
There were also the Bengal carbines sold in the 70's, 12 bore, 25" barrel & captive swivel ramrod, I had one, it was not good quality but it gave me a lifelong love of blackpowder. Proper muzzleflash with that short tube!