The Savage M720 existed as a semi-automatic, repeat-fire shotgun delivered by the Savage Arms Company. The company held a history dating back to 1894 when the Jamaican-born Arthur W. Savage formed the concern as the Savage Arms Company. Savage then bought out the competing Stevens Company in 1920 and then began playing a role in World War 2 (1939-1945) where it participated in manufacture of Lee-Enfield No. 4 Mk I rifles for the British government during the early going. By the time of American involvement in the war, the company then turned to manufacture of the M720 (Model 720) which was eventually procured across 14,527 units by the U.S. government. These served in the traditional short-ranged combat role, as a security weapon and aerial gunnery trainer. Procurement spanned from 1942 into 1945.
Unlike traditional pump-action slide shotguns, the Stevens M720 was a semi-automatic offering built upon the patents of the great American gunsmith John Moses Browning (1855-1926). As such, the forend was fixed around the tubular magazine and the receiver decidedly rectangular - indeed mimicking the lines of the John Browning-designed Remington "Model 11" auto-loader of 1905. The pistol grip was integrated to the shoulder stock which were both of wooden construction (as was the forend). The barrel was seated above the magazine and inserted into the forward face of the receiver in the usual way. A charging handle and ejection port were offset to the right side of the body while the loading port was under the receiver with easy access to the tubular magazine. The trigger unit was underslung in a rifle-style arrangement near the grip handle.
Unlike other wartime shotguns, the M720 was not fitted with bayonet lugs or a heatshield due to the particular semi-automatic function at play. As such, no "Trench Gun" versions were completed as seen in other notable lines. Instead, the basic "Riot Gun" form was accepted with its shortened barrel and used by security personnel. Conversely, long-barreled forms were also purchased and these used for aerial gunnery training leading such organizations such as the United States Navy to also take on stocks of the type.