Bren Light Machine Gun

The Bren, usually called the Bren Gun, was a series of light machine guns adopted by Britain in the 1930s and used in various roles until 1991. While best known for its role as the British and Commonwealth forces' primary infantry light machine gun (LMG) in World War II, it was also used in the Korean War and saw service throughout the latter half of the 20th century, including the 1982 Falklands War and the 1991 Gulf War. Although fitted with a bipod, it could also be mounted on a tripod or vehicle-mounted.

The Bren was a modified version of a Czechoslovak-designed light machine gun, the ZB vz. 26, which British Army officials had tested during a firearms service competition in the 1930s. The later Bren featured a distinctive curved box magazine, conical flash hider and quick change barrel. The name Bren was derived from Brno, the Czechoslovak city where the Zb vz. 26 was originally designed, and Enfield, site of the British Royal Small Arms Factory).

In the 1950s the Bren was rebarrelled to accept the 7.62x51mm NATO cartridge. It was replaced in the British Army as the section LMG by the L7 general purpose machine gun (GPMG), a heavier belt-fed weapon. This was in turn supplemented in the 1980s by the L86 Light Support Weapon firing the 5.56x45mm NATO round, leaving the Bren in use only as a pintle mount on some vehicles.

Development
During the early 1930s, the British Army subjected several designs of light machine gun to competitive trials. Among the weapons that were submitted for the trials were the Madsen, Browning Automatic Rifle (BAR), the Neuhausen KE7 and the Vickers-Berthier. The Vickers-Berthier was later adopted by the Indian Army and also saw extensive service in WWII.

Following these trials, the British Army adopted the Czechoslovak ZB vz.26 light machine gun manufactured in Brno in 1935, although a slightly modified model the ZB vz. 27 rather than the ZB vz. 26 had actually been submitted for the trials. A licence to manufacture was sought, and the Czech design was modified to British requirements. The major changes were in the magazine and barrel. The magazine was curved in order to feed the rimmed .303 British cartridge, a change from the various rimless Mauser-design cartridges such as the 7.92 mm Mauser round previously used by Czech designs. These modifications were categorised in various numbered designations, ZB vz. 27, ZB vz. 30, ZB vz. 32, and finally the ZB vz. 33, which became the Bren.

The Bren was a gas-operated weapon, which used the same .303 ammunition as the standard British rifle, the Lee-Enfield, firing at a rate of between 480 and 540 rounds per minute (rpm), depending on model. Each gun came with a spare barrel that could be quickly changed when the barrel became hot during sustained fire, though later guns featured a chrome-lined barrel which reduced the need for a spare.

The Bren was magazine-fed, which slowed its rate of fire and required more frequent reloading than British belt-fed machine guns such as the larger .303 Vickers machine gun. However, the slower rate of fire prevented more rapid overheating of the Bren's air-cooled barrel, and the Bren was several pounds lighter than belt-fed machine guns which typically had cooling jackets, often liquid filled. Because it was more easily portable, it could be fired on the move and from standing or kneeling positions, though not as sometimes portrayed in comics and movies, "from the hip" as there would be considerable muzzle climb. The magazines also prevented the ammunition from getting dirty, which was more of a problem with the Vickers with its 250-round canvas belts