It’s not that it’s a black powder muzzleloader. It’s what it shoots out the muzzle, how heavy and how fast. That’s a huge bore . . . Likely one inch, with a lot of powder behind it and no real way to hold on to it. It will have a huge recoil. A 1 inch bore ball would weigh about 3.4 ounces. Move it out of the muzzle at say 1100 feet per second from a gun weighing six or seven pounds, and you will still have a respectable kick.
Fyi, I belong to a UK shooting forum & one of the members posted a photo of the over/under EIGHT GAUGE muzzleloading shot-PISTOL that he built, as a “big lad’s toy”.
I cannot even imagine what the recoil of that BEAST would be like & neither would I want to find out by firing it.= 3 ounces of shot, in front of a heavy charge of FG black-powder in each barrel.
(He has also built & hunts waterfowl with a 3-inch bore PUNT-GUN, that is mounted in a 16-foot “gunning-skiff”.)
Yours, TMN78247