Just thought this would be interesting. I think we’ll all recognize this weapon:
Pepperbox Gun
As far as I know, they were never extended into full-length rifles like Kruber’s Repeater Handgun. They were a pretty late invention, being popular just before revolvers became popular in the 19th century.
Speaking of revolvers, though, I thought this was an interesting actual revolver that was made in 1597:
Stopler Revolver
I could imagine Bardin getting something like that at some point - as more of a high-stopping power weapon like we think of revolvers today, though maybe with a shorter range.