Developed in Britain, the .303 British cartridge is a rimmed rifle round that was first used in 1888. Designed for the Lee-Metford rifle, the .303 British round was eventually adapted to use smokeless powder. As the standard British and Commonwealth round, the .303 British round saw much use from 1889 until the 1950s. The .303 British round is also commonly referred to as just 303 British or 7.7x56mmR.
The .303 British ammunition, also known simply as .303 British or 7.7x56mmR, has its origins in the late 19th century, serving as the United Kingdom's primary cartridge for over six decades. Developed in the 1880s, it was first used in the Lee-Metford rifle and later in the iconic Lee-Enfield series of rifles. The .303 played a pivotal role in both World Wars, being used in various platforms including rifles, machine guns, and even early aircraft-mounted weapons. Renowned for its accuracy and reliability, this rimmed cartridge was gradually replaced in the mid-20th century by more modern rimless cartridges, but it remains a popular choice among vintage firearm enthusiasts and hunters today.
