Vektor R4
The Vektor R4 is a 5.56×45mm assault rifle designed in 1979 based on the IMI Galil rifle. It entered service as the standard service rifle of the South African Defence Force (SADF) in 1980. The R4 replaced the R1, a variant of the 7.62×51mm FN FAL. It was produced by Lyttelton Engineering Works (LIW, "Lyttelton Ingenieurswerke"), now Denel Land Systems. The weapon is a licensed variant of the Israeli IMI Galil assault rifle with several modifications; both the stock and magazine are now made of a high-strength polymer and the stock was lengthened, adapting the  weapon for the average South African soldier. Other detailed differences include the R4's lack of a carry handle and a number of improvements made to its internal operating mechanism. Design details. Operating mechanism. The R4 is a selective fire, gas-operated weapon that fires from a closed bolt. As with the Galil parent weapon, the operating system is derived from that of the AK-47. It uses ignited powder gases channelled through a vent in the barrel to drive a long stroke piston located above the barrel in a gas cylinder to provide power to the operating system. The weapon  features a self-regulating gas system and a rotary bolt breech locking mechanism (equipped with two locking lugs), which is rotated by a helical camming groove machined into the bolt carrier that engages a control pin on the bolt. Extraction is carried out by means of a spring-loaded extractor contained in the bolt and a protrusion on the left guide rail inside the receiver acts as the fixed ejector. Features. The R4 is hammer-fired and uses a trigger mechanism with a 3-position fire selector and safety switch. The stamped sheet steel selector bar is present on both  sides of the receiver and its positions are marked with letters: "S"— indicating the weapon is safe, "R"—single-fire mode ("R" is an abbreviation for "repetition"), and "A"—fully automatic fire. The "safe" setting disables the trigger and secures the weapon from being charged. The R4 is fed from a synthetic box magazine with a 35-round cartridge capacity (designed to use the 5.56×45mm NATO cartridge with the M193 projectile) loaded in a staggered configuration. During the 1980s South African troops were issued with one 50-round magazine as well. The flash suppressor is slotted and doubles as an adapter  for launching rifle grenades. Bolted to a bracket in the gas block, under the barrel, is a lightweight folding bipod (folds into the handguard), which includes a wire cutter in the hinge. The R4 has a side-folding tubular stock, which folds to the right side of the receiver. The rifle's handguard, pistol grip, magazine, stock arms and shoulder pad are all made from a synthetic material, making it lighter in weight than the equivalent original Galil model which uses heavier metal and wood in these components. For regular field maintenance and cleaning, the firearm is disassembled into the  following components: the receiver and barrel group, bolt carrier, bolt, return mechanism, gas tube, receiver dust cover and magazine. Sights. The rifle has conventional iron sights that consist of a front post and a flip-up rear sight with 300 and 500 m apertures. The front sight is adjustable for windage and elevation and is installed in a durable circular shroud. The rear sight is welded at the end of the receiver's dust cover. For nighttime use, the R4 is equipped with self-luminous tritium light dots (exposed after placing the rear sight in an intermediate position) installed in  a pivoting bar to the front sight base, which folds up in front of the standard post and aligns with two dots in the rear sight notch. Accessories. The R4 is issued with spare magazines, a cleaning kit and sling. Upgrade. DLS has introduced remanufactured models of the R4, R5, R6 that have Picatinny rails. DLS has also introduced grenade launchers, grips and other underbarrel attachments. Variants. The South African Navy, South African Air Force, South African Military Health Service, and South African Police Service adopted a short carbine version of the 5.56 mm Galil SAR, which was license-manufactured  as the R5. The R5, when compared to the larger R4, has a barrel that is shorter, together with a shorter gas system and handguard. It also lacks a bipod, and the flash hider does not support rifle grenades. In the 1990s, an even more compact personal defence weapon variant of the R5 was developed for armoured vehicle crews, designated the R6, which has a further reduced barrel and a shortened gas cylinder and piston assembly. This reduced the barrel length to . Denel developed prototypes for the R7 and R8, a heavy barrelled squad automatic weapon and a locally produced  Micro-Galil, respectively, but it is unclear whether these entered production. LIW/DLS also introduced a line of semi-automatic variants of the R4, R5 and R6 called the LM4, LM5 and LM6 respectively, built for civilian and law enforcement users. The rifles were marketed by Musgrave, with the joint venture between the Lyttelton and Musgrave conferring the rifle's "LM" prefix.