The Browning Automatic Rifle (BAR) was an automatic rifle primarily used by the U.S. military during World War II, having been originally designed by John Browning in 1917 for World War I. Here are some key details about the BAR during WWII: Design and Features: • Model: The most commonly used version in WWII was the M1918A2. • Caliber: The BAR was chambered in .30-06 Springfield, which was the standard U.S. rifle and machine gun round at the time. • Operation: It was a gas-operated, air-cooled automatic rifle with a selectable fire rate (slow and fast automatic fire). • Weight: Weighing around 20 pounds, it was quite heavy for an infantryman to carry, but it was significantly more portable than a crew-served machine gun. • Magazine: The BAR used a 20-round detachable box magazine, which allowed for bursts of fire but limited sustained fire compared to belt-fed machine guns.