>>64362676
>"There was a pump action low pressure black powder electrically primed shotgun. The plastic casing had a rim that came in contact with contacts in the chamber (or something like that) that then ignited the powder."
Sounds very cool, have a name?
>"Paper cartridges were used extensively with all muzzle loading firearms including cap and ball revolvers, yes
I was talking about repeating arms"
I made that comment to let you know that I really don't know any solutions, but it has only now popped into my mind that the Harmonica gun exists. Perhaps this is the answer?