Bullpup machine gun proved to be unreliable
by MATTHEW MOSS
In 1970, the British Army began to develop its next generation of infantry small arms. The Enfield Weapon System project aimed to produce a five-millimeter bullpup rifle and a light machine gun.
The Royal Small Arms Factory at Enfield got to work. After many changes to the design and caliber, the eventual result was the SA80 rifle — also known as the L85 Individual Weapon — and the L86 Light Support Weapon. Both of these weapons were essentially ArmaLite AR-18s in a bullpup configuration.
But the LSW turned out to be a largely inadequate weapon.
Between 1970 and 1985, the Light Support Weapon went through a series of design iterations and revisions. Initially, the “00 Series” LSW differed little from the SA80 rifle in order to facilitate parts commonality, but as the design developed it became clear that major changes were necessary.
The “0 Series” LSW from 1975 had a heavier, quick-change barrel. The bolt carrier was slightly heavier, the plastic stock differed and the gas plug had an additional port. By the time of the weapon’s first evaluation, parts commonality with the rifle had dropped to 80 percent.
As the LSW was a bullpup, there were initially two variants — the XL65E4 for right-handed operators and the XL69E1 for lefties. These designs differed in that the charging handle and ejection port were on opposite sides of the receiver. The army eventually abandoned the left-handed XL69E1, however, as all but a small percentage of left-handed shooters could be trained to fire adequately from the right shoulder.
Between 1977 and 1979, NATO held ammunition trials in order to select a smaller-caliber cartridge to complement the existing 7.62-by-51-millimeter cartridge. The trial pitted variations of the U.S. 5.56-by-45-millimeter round against Britain’s 4.85-by-49-millimeter cartridge and West Germany’s 4.7-millimeter caseless ammunition.
NATO selected F.N.’s 5.56-by-45-millimeter SS109 cartridge, which the alliance decided had the best all-around performance. As a result, the British had to rechamber the I.W. and LSW in the new 5.56-45-millimeter NATO round.
In late 1980, the British renamed the Enfield Weapon System program “Small Arms for the 1980s,” or SA80.
Officials initially envisioned that the LSW would fire from a closed bolt for semi-automatic fire and from an open bolt for fully-automatic fire. However, by 1980 Enfield had abandoned this idea — and developed prototypes that fired from both a closed and an open bolt.
Enfield built an open-bolt version of the LSW designated XL73E2, and a closed-bolt weapon using the same mechanism as the I.W. and designated XL73E3.
Following Ordnance Board and user trials in 1981 and 1982 — during which the XL73E2 suffered critical failures and a marked loss of accuracy after firing 1,600 rounds — officials selected the closed-bolt XL73E3. But it needed further improvement.
After acceptance trials in 1984, the army again deferred introduction of the LSW due to its inability to group consistently during automatic fire at various ranges. This was a major issue, considering the weapon was supposed to replace the L7 GPMG at the section level as a support weapon.
The army ordered Enfield to improve the design while the Ministry of Defense explored foreign designs as possible replacements. Comparative trials tested the F.N. Minimi, HK13 and the light-machine-gun variation of the Steyr AUG.
The AUG proved to have the best accuracy and was most similar to the LSW in operational concept. The military passed over the AUG, however, because its magazine was proprietary to the designer. Ironically, the British Army would later adopt the F.N. Minimi as the L108A1/L110A2.
In an effort to improve accuracy, Enfield added a rear grip and butt strap to give the gunner greater control. Another of the LSW’s identifying features, its steel “outrigger” that runs beneath the barrel, was also added. This improved accuracy and allowed the bipod to attach at the muzzle. These changes improved the weapon but further reduced parts-commonality.
Following these changes, the army provisionally accepted the LSW in September 1984. The Royal Small Arms Factory at Enfield delivered the first weapons in October 1985. Each LSW cost approximately £350, plus another £138 for the weapon’s optical sight and mount.
The 5.56-millimeter LSW fed from standard 30-round magazines and was gas-operated with a rotating bolt. Between 1987 and 1992, the Ministry of Defense considered adopting the 100-round BETA C-Mag, allowing the weapon to sustain continuous suppressing fire. But problems with the feeding of the last 15 rounds caused the Ministry to lose interest.
Later, officials discovered that British ammunition made at Radway Green developed lower pressures and caused the cyclic rate to drop, causing the feed failures. It wasn’t the magazine’s fault.
The weapon’s overall length was 89 centimeters. It weighed 5.52 kilograms when loaded. It had a cyclic rate of 700 to 800 rounds per minute and, like the SA80/L85, fired from a closed bolt. While the LSW proved to be extremely accurate when firing single shots, it suffers split groups when firing in fully automatic.
The L85 and L86 LSW first saw combat during the 1991 Gulf War. Post-war reports found that the LSW had experienced extraction problems and had suffered more stoppages than the L85 had done. As a result, in 1995 the Ministry of Defense requested that Heckler & Koch carry out an appraisal of the L85 and L86, with an eye toward improving both weapons.
Work on would become the A2 variant began in June 2000 with a budget of £90 million to overhaul 200,000 weapons. Heckler & Koch completed the modifications in February 2006, improving the magazines, the friction inside the action, the spring strength and the extractor.
The improved A2 variants first saw action in Afghanistan. Despite the modifications, user confidence in the LSW was low and the Ministry of Defense moved to replace the weapon at section level with the L110A2 — the paratroop version of the F.N. Minimi. When operations began in Iraq in 2003, the Ministry purchased a further 700 Minimis, issuing them in place of LSWs.
With British troops fighting at longer and longer ranges — sometimes exceeding 500 meters — the military decided to add a semi-automatic designated marksman’s rifle at the fire-team level — two DMRs for each eight-man infantry section. The LSW’s proven semi-automatic accuracy saw it temporarily thrust into a new role as a “Long Range Rifles.”
It didn’t last. In 2010, the British Army adopted the 7.62-by-51-millimeter L129A1 Sharpshooter rifle made by Lewis Machine & Tool, receiving 1,500 of the new weapons by 2013. Nagging concerns over the LSW’s reliability and its poor performance as a light support weapon compelled the army to quietly relegate the old LSW to regimental armories.
Originally published at www.historicalfirearms.info.