“It can’t actually launch a projectile.”
When I was a kid, we had these great cap guns that looked just like old Colt revolvers. There were “bullets” You had to open the cylinder, take out the “cartridge,” Pull out the “bullet,” and stick a round cap on them, and reassemble. You got 6 shots! Not a whole roll.
Well, the “bullets” had a hole in them, and I discovered that a BB fit into the hole perfectly! Instead of using one sticky cap, I’d use ten! It would fire the BB about a dozen feet, but with virtually no force behind it.
Those cap guns were cool because you had to optimize your shots, or you were shot, and ended up “dead” until the count of 50.
Sounds like the Fanner 50. My dad had one that I inherited. The original came with a holster for a right hander. He was left handed and my grandparents had a holster made for a left hander (Nocona Boot company).
http://www.nicholscapguns.com/mattel4.htm