I just bought one from a client on Tuesday. I had never seen a rotating/swivel breech before. Unfortunately the steel is covered with black paint, enamel I believe. I had to use some xxxx steel wool and solvent to uncover the manufacturer. I have not located the serial number yet. Here is what I found out, from the markings, J. Rupertus Philda, Pa USA patent NOV121878. The patent number is #209925 and below are the drawings. I'd be glad to post any links or info I can find. Do you know how I can remove the paint without destroying the Damascus barrel?