I have one as well! Does yours have the Swastikas on it? And does it have any manufacturers name on it. Mine does not due to the fact if they were captured they did not want the allied forces to know where the manufacturing plant was.
I also have the original holster with Swastikas on it. Mine was taken from a German Officer on the Russian front.
As far as shooting it! I try to shoot about 10 rounds a year through mine and then clean it just for nostalgic purposes. I like history and love to shoot it on occasion something about shooting it.
I have been offered $1600 for it and the holster, so yours is definitely worth some money if it is of military issue.