Soon after leaving ArmaLite, Eugene Stoner, one of the United States' most prolific modern military small arms designers, responsible for the design of the ArmaLite AR-15/M16 assault rifles, ArmaLite AR-10 battle rifle and Armalite AR-7 survival rifle, among others, devised a concept for a modular weapon that would be built around a common receiver and certain interchangeable components and could be transformed into a rifle, carbine or various machine gun configurations by simply fitting the appropriate parts to the basic assembly.