What is the designation for the squad automatic weapon in the U.S. Army?

The designation for the squad automatic weapon in the U.S. Army is the M249. This weapon, also known as the Squad Automatic Weapon (SAW), is specifically designed to provide infantry squads with a high-volume, sustained automatic fire capability. The M249 is chambered for the 5.56x45mm NATO cartridge and feeds from a belted ammunition system, allowing for a high rate of fire while remaining relatively lightweight and portable for infantry soldiers.

The M249 fulfills the role of providing suppressive fire to support maneuvering units in combat operations, making it an essential asset for any infantry squad. Its design allows for both bipod and tripod mounting, enhancing stability during sustained fire situations.

In contrast, the M240B serves as a medium machine gun and is used primarily for different combat roles, while the M16 and M4 are standard rifles that serve as individual weapons, not specifically designated as automatic weapons within a squad. Thus, the M249 is distinctly recognized as the squad automatic weapon due to its specific functions and capabilities in supporting infantry tactics.