Whats up with these barrel markings

[Doubs]

Originally Posted by Lugerdoc

Scott, I suspect that this replacement barrel was added by the Norweigen arsenal at Koeignsburg (C/K marking). TH

Good eye, Tom.

I, too, thought it may be Norwegian or other Scandinavian country's marking. Unfortunately, my Standard Dictionary of Proof Marks doesn't include Norway and the internet is no help.