Details

The L4A3 Bren, was the standard section-level LMG of the UK Army and Navy from 1958 until withdrawal in 1992. Unlike many weapons adopted by a major army, the L4s were not purpose-built weapons, but instead conversions of earlier weapons. The L4A3 (later A4) specifically were a conversion of the Mk2 Bren to 7.62mm NATO, the A2/A4 were the same but based off the Mk3.
The mechanical origins of the L4 come from the WW2 project of clandestinely providing Bren LMGs converted to 7mm Mauser by Inglis of Canada to the Chinese resistance against Japanese occupation.However, unlike the Inglis conversions, the bolts for the L4 were purpose made, with stronger extractors.

With the introduction of the L1A1 SLR as the main Infantry Rifle, the L4 was made to be compatible with the rest of the section for simplified logistics, and as such was made to feed from what was basically a 30 Round inch-pattern FAL magazine. To accomplish this with the shorter and wider mag, the walls of the magazine well were reamed out, and an insert block containing a new magazine release housing and a shelf were inserted.These changes were found out on the L4A1 to make the receiver walls weak and prone to deformation. As a result the shelf and magazine well walls were reinforced with a plate riveted through to the outside on all later models.

The last major changes to achieve the base specification were to replace the Stainless Steel conical flash hider with a 5-port starburst muzzle brake similar to the ones on the SLR, and to issue fresh recontoured stocks and carrying handles.

With these, the general L4 spec was done and applied to both Mk2 and 3 Brens in roughly equal measure.

The eventual response to the L4 in service was largely positive. While it was heavy for a shoulder-arm, and magazines did mean more breaks in sustained fire than a Belt-fed LMG, its precision and controllability meant that it retained the Bren’s long-standing popularity with the troops. It was not to last, though. The L4s were always intended as a stopgap until something better came along, and during the late 1980s the Brens were eventually completely supplanted in use by L7, L108 and L110 machine guns- the last reserves being made obsolete in early 1992.

The NIArms Bren set is currently one model of Bren -the L4A3-, with the intent to fill the roster at a later date.