Sjögren shotgun

The Sjögren Inertia Shotgun is a 12 gauge semi-automatic shotgun designed by the Swedish inventor Carl Axel Theodor Sjögren, manufactured in Denmark by Håndvåbenværkstederne in 1909. It used an inertia system later revived by the Italian firm Benelli and today widely used in shotguns. It saw very limited service in World War I by both the allies & the central powers, and service with other armies and resistance groups of the interwar period and World War II.