What is the caliber of the M2 ammunition?

The M2 ammunition, commonly known as .50 caliber, is specifically designed for the M2 Browning machine gun. This caliber was developed to provide substantial firepower and is used for various applications, including anti-aircraft and anti-materiel roles. The .50 caliber designation refers to the bullet diameter of approximately 0.50 inches (or 12.7mm), which allows it to deliver significant destructive capability against both personnel and equipment.

In contrast, the other options represent different calibers used in various firearms but are not associated with the M2 machine gun. For example, .30 caliber ammunition is typically linked to older machine guns and rifles, while 7.62mm ammunition is used in rifles like the M14 and various types of machine guns. The 5.56mm cartridge is primarily used in infantry rifles such as the M16 and M4. None of these match the specific caliber designation of the M2 ammunition, reinforcing that .50 caliber is indeed the correct choice.