The later Bren gun featured a distinctive top-mounted curved box magazine, conical flash hider, and quick change barrel.

This was supplemented in the 1980s by the L86 Light Support Weapon firing the 5.56×45mm NATO round, leaving the Bren gun in use only as a pintle mount on some vehicles.

The Vickers was heavy and required a supply of water to keep it in operation, which tended to relegate it to static defence and indirect fire support.

The Lewis, although lighter, was still heavy and was prone to frequent stoppages: its barrel could not be changed in the field, which meant that sustained firing resulted in overheating until it stopped altogether.

Various new models of light machine gun were tested as they became available, and in 1930, a further set of extensive trials commenced, overseen by Frederick Hubert Vinden.

The last did not meet high requirements for durability and reliability, mainly because gunpowder residue from British cordite was obstructing the gas tube (ZB vz.

[9] The Vickers–Berthier was later adopted by the Indian Army because it could be manufactured at once, rather than wait for the British Lewis production run to finish; it too saw extensive service in World War II.

[9] After additional trials in early 1934, more samples were ordered during the summer of 1934, and on May 24, 1935, the licence for British manufacture was finally acquired, and the design was adopted under the Bren name.

[citation needed] The Bren was a gas-operated weapon using the same .303 ammunition as the standard British bolt-action rifle, the Lee–Enfield, firing at a rate between 480 and 540 rounds per minute (rpm), depending on the model.

[18] On occasion, a Bren gunner would use his weapon on the move supported by a sling, much like an automatic rifle, and from standing or kneeling positions.

A Victoria Cross was awarded to Private Bruce Kingsbury for such use at Isurava, New Guinea, in 1942, during the Australians' fighting retreat from Kokoda.

[22] For a light machine gun of the interwar and early World War II era, the Bren was about average in weight.

[25] In general, the Bren was considered a reliable and effective light machine gun, though in North Africa it was reported to jam regularly unless kept very clean and free of sand or dirt.

It was "by general consent the finest light machine gun in the world of its period, and the most useful weapon provided to the (French) "maquis" ... accurate up to 1,000 meters, and (it) could withstand immense maltreatment and unskilled use.

The Bren Mk II design simplified production by replacing the drum rear sight with a ladder design, making the bipod legs non-adjustable, simplifying the gun butt, reducing the use of stainless steel, among other steps that reduced the cost by 20% to 25%; Mk II was approved in September 1940 and entered production in 1941.

In Australia, the Lithgow Small Arms Factory in New South Wales began building Bren guns in 1940; a total of 17,249 were built.

[28] A tripod mount with 42 degrees of traverse was available to allow the Bren to be used on "fixed lines" of fire for defensive shooting at pre-determined areas in the dark or if obscured by fog or smoke.

[29] The Bren could not be used as a co-axial weapon on tanks, as the magazine restricted its depression and was awkward to handle in confined spaces, and it was therefore used on a pintle mount only.

(The belt fed Vickers or Besa, the latter being another Czechoslovak machine gun design adopted by the British, were instead used as co-axial weapons.)

An unfortunate problem occurred when the Bren was fired from the Dingo Scout Car; the hot cartridge cases tended to be ejected down the neck of the driver, whose position was next to the pintle.

Many 7.92 mm ZB light machine guns were shipped to China, where they were employed first against the Japanese in World War II, and later against UN forces in Korea, including British and Commonwealth units.

Completion of the move to a 5.56 mm NATO cartridge led to the Army removing the Bren/L4 from the list of approved weapons and then withdrawing it from service.

[citation needed] The Mark III Bren remained in limited use with the Army Reserve of the Irish Defence Forces until 2006, when the 7.62 mm GPMG replaced it.

Features: An Enfield-made .303 Bren Mk 1 was converted to 7.92mm in 1938 due to the suggestion of a possibility of a British Army change over to a rimless cartridge for machine guns being mooted.

A simplified version of the Mk1 more suited to wartime production with original design features subsequently found to be unnecessary deleted.

[39] The Inglis version of the Bren Mk 2 chambered for the .30-06 (7.62 mm) cartridge and known as the M41 was also manufactured in Taiwan after the end of the Chinese Civil War.

Unlike the Bren, the Besal was full automatic only rather than select fire and lacked a cocking handle, using the pistol grip instead.

[51][52] In 1942, the Ishapore Arsenal began to produce Bren guns, and continued to do so long after the end of World War II, also manufacturing variants in 7.62×51mm NATO.

[51] A shadow factory for Ishapore was set up at Kanpur and produced .303 Brens before it was later rechambered to fire 7.62 NATO ammo in 1964[53][54] as the 1A LMG.

[55] In 1940, the Lithgow Small Arms Factory in New South Wales began to manufacture Bren guns, producing a total of 17,249 by 1945.