The shotgun and combination set is made by Louis Hellfritsch of Berlin.

I do not have a brass case only a description by the owner of the chamber which was described as 11mm by 1 1/2 inch long, and the bores are in poor condition. Shotgun chambers are 2 1/2". Set of shotgun barrels and second set of cape barrels.

Any ideas?

Also could the shotgun/rifle cape barrel set be used as a project to build something else?

The 10.4x38Rmm Swiss Vetterli sounds like a possibilty for the original chamber.

What sort of ballistics did it achieve? Was it originally black powder?