6 mm SAW

The 6mm SAW describes an experimental series of cartridges developed in the 1970s for the U.S. Army. The cartridges were produced in a variety of sizes and from a variety of materials. The intent was to develop a cartridge that would replace all 5.56×45mm NATO weapons as well as most 7.62×51mm NATO rifles and machine guns in the U.S. military. Eventually, the 5.56mm was retained and only the machine gun portion of the SAW (Squad Automatic Weapon) competition was successful. That program led to the M249 light machine gun.

Note that the dimensions listed to the right are for 6×45mm SAW rounds. Three versions were produced for testing in the early 1970s. An aluminum-cased version was developed, as well as the 6mm SAW Long which was slightly longer (by about 5 mm)