Ed nailed it. There is also a Swiss conversion unit. It is used as a single shot. It takes a little "spoon" to insert the round into the barrel adapter and then you have to poke out the spent cartridge with a rod.
I do not have a 4mm adaptor, but I wouldn't mind adding a box of these to my Luger odds and ends if you decide to part with them.
__________________
If it's made after 1918...it's a reproduction
|