The L85 or SA80 (Small Arms for 1980s) is the standard frontline rifle of the British Military. It is a gas operated bullpup design which is accurate and has very little recoil. It comes fitted with the SUSAT x4 optical sight, further enhancing its accuracy. Its undoubtedly fine design was let down by both engineering defects and a lack of durability in active-service. The A2 variant was produced in 2000 by Heckler & Koch, implementing a series of redesigns and upgrades on the existing stock of 200,000 L85’s in service in the UK. The original design of the L85 / SA80 was done by the Enfield Royal Small Arms Factory, and later production was handled by Royal Ordnance’s Nottingham factory.

The receiver of the L85 is made from stamped sheet steel, reinforced with welded and riveted machined steel inserts. The gas operated action has a short stroke gas piston, located above the barrel. The gas piston has its own return spring. Gas system has a three-positions gas regulator, one position for a normal firing, second for a firing in adverse conditions and the third for launching the rifle grenades (gas port is shut off). The machined bolt carrier rides inside the receiver on the two parallel steel guide rods, with the single return spring placed above and between the guide rods. The typical rotating bolt has 7 lugs that locks into the steel insert in the receiver, just behind the barrel breech. The charging handle is attached to the right side of the bolt carrier, and prior to A2 upgrade caused some problems by reflecting the ejected cases back into the action, thus causing stoppages. In the L85A2 configuration the charging handle was redesigned to avoid such problems. The charging handle slot is covered by the spring-loaded dust cover. The bolt and its extractor claw also were upgraded in the L85A2, to achieve more reliable extraction of the spent cases.

The L85 can be fitted with the proprietary knife-type multipurpose bayonet. L85A2 rifles also can be fitted with 40mm under-barrel grenade launcher, using special handguard. Launcher is made in Germany by Heckler & Koch.