Yes you are refering to the Liberator pistol. They made millions of the things to pass out to freedom fighters behind the lines in Europe. The idea was you walk up behind a German soldier, shoot him in the back of the head, and take his rifle. They never distributed many of them, and ended up destroying many after the war. They are rare, and very collectable so expect to pay a premium for one today. If I recall right they take over 5 minutes to load.