Like other European nations during the Cold War, the Austrian Army made use of the excellent Belgian FN FAL Battle Rifle firing the 7.62x51mm NATO cartridge. These weapons were produced locally under license as the "StG 58" (Sturmgewehr 58). The original FN FAL was introduced in 1954 and was ultimately produced in over 2,000,000 examples, seeing action in countless conflicts thereafter with widespread circulation still apparent today. Its design was rather robust and her full-power rifle cartridge was a proven man-stopper.
By the 1975, the weapon system was already twenty years old. As such, design work on the Steyr AUG ("Armee Universal Gewehr" or "Army Universal Rifle") series of Austrian origin progressed throughout the middle and latter portion of the 1970s. After evaluation of the system, the Austrian Army formally adopted the 5.56mm weapon as the "StG 77" (Sturmgewehr 77) in 1977 (hence the weapon's designation). Quantitative production ensued beginning in 1978 to which the automatic weapon entered Austrian military service in 1979 and has since gone on to be used in the militaries, special forces groups and security units of various global entities.
The AUG was designed around the "bullpup" configuration concept in which all of the major internal working components of the action - and its corresponding magazine feed/ejection system - were concentrated to the rear of the pistol grip. While the style is notably gaining in popularity today, the bullpup configuration - when used in a frontline service rifle - was something of a drastic departure for the time. The rear-set placement of the internal workings allowed engineers to feature a full-length barrel within a more compact overall form. The heavier stock, when properly positioned against the body, allowed for a firmer three-point hold of the weapon, making its use in confined spaces more acceptable than traditional long guns. Accuracy at shorter ranges was improved and an operator could raise his weapon (in response) quicker than a traditional infantryman with a conventionally-arranged long gun could. Considering the ranges at which infantryman often engaged their targets - particularly in urban settings - this made the bullpup approach a rather sound one.
The Steyr AUG took on a most futuristic appearance for its time, showcasing well-contoured lines, minimal external detailing and proven internal functionality. The receiver was a large plastic (fiberglass-strengthened polyamide 66) assembly covering the various metal (aluminum and steel) parts within. The receiver also made up the fixed buttstock and sported the magazine feed as well as the ejection port - all aft of the pistol grip. The pistol grip itself was integrated cleanly into the design and ergonomically engineered for a firm hand hold. The grip was protected by a slim hand guard while the large curved trigger could clearly be identified. A safety was within easy reach of the firing hand. The forward region of the weapon contained the all-important barrel which protruded a distance ahead. A folding vertical foregrip was set beneath the barrel at its base and this grip was used to change out the "quick-change" barrel as needed. Over the top of the weapon was a two-point mounting system for the standard-issue optics (a 1.5x Swarovski scope) that doubled as a carrying handle. This installation could be removed and replaced by a standard Picatinny mounting rail (by way of an alternative receiver casting) for custom optics and accessories in follow-up production models. The steel barrel was capped by a slotted or three-pronged flash hider. In all, the AUG could be field-stripped into just six key components. Ambidextrous operation was made possible by covering the right ejection port and revealing the left side port with a left-handed bolt also replaced the standard right-hand bolt. A bayonet mounting and underslung grenade launcher (M203 40mm) were optional and broadened the tactical usefulness of the AUG family in-the-field. The barrel (16- and 20-inch flavors) was also designed to fire rifle grenades.
The Steyr AUG uses a short piston stroke, gas operated action, with the gas piston mounted inside the compact gas block, which is fixed to the barrel. The gas cylinder is offset to the right from the barrel. Gas piston has its own return spring, contained inside the gas block. The gas system features a three positions gas regulator, which allows for two open positions (for normal and fouled conditions) and one closed position (for launching the rifle grenades). The gas block also contains a barrel fix / release lock and a front grip hinge. Each barrel has eight lugs, that lock into the steel insert in the receiver, and there's four basic barrel patterns for the Steyr AUG: standard rifle barrel is 508 mm (~20 in) long. "Compact" or "Submachine gun" barrel is 350 mm (13.8 in) long, "Carbine" barrel is 407 mm (16 in) long, and the heavy / LMG (light machine gun) barrel is 621 mm (24.4 in) long. On each rifle barrels can be exchanged in the matter of seconds. Each barrel is fitted with the flash hider, and the heavy 621 mm barrel also is fitted with lightweight folding bipods. There's no bayonet lug on Austrian service rifles, but it can be installed if required.
Barrel replacement procedure, as noted above, takes only few seconds (assuming that the shooter has the spare barrel handy). To remove the barrel, one must take off the magazine, and clear the rifle by operating the cocking handle. Then, grasp the barrel by the front grip, push the barrel retaining button at the gas block, and rotate the barrel and pull it out of the rifle. To install a new barrel, simply push the barrel down into the front of the receiver all the way and then rotate it until it locks. The rifle now is ready to be loaded and fired.
The bolt system consists of the bolt carrier, which has two large hollow guide rods, attached to its forward part. The left rod also serves as a link to the charging handle, and the right rod serves as the action rod, which transmits the impulse from the gas piston to the bolt carrier. The rotating bolt has 7 locking lugs, claw extractor and a plunger-type spring loaded ejector. Standard bolt has its extractor on the right side, to facilitate right-side ejection, but the left-side bolts (with mirrored positions of extractor and ejector) are available for those who need left-side ejection. The two return springs are located behind the bolt carrier, around the two string guide rods, that are located inside the bolt carrier guide rods. The cocking handle is located at the left side of the gun and normally does not reciprocate when gun is fired, but it can be solidly engaged to the bolt group if required by depressing the small button on the charging handle. On the latest Steyr AUG A2 variant, the charging handle was made folding up and of slightly different shape. The Steyr AUG action features a bolt stop device, that holds the bolt group open after the last round of ammunition from the magazine is fired. To release the bolt after the magazine replacement, one must pull the charging handle.
The hammer unit is made as a separate assembly and almost entirely of plastic (including the hammer itself). Only springs and pins are steel. The hammer unit is located in the butt and is linked to the sliding trigger by the dual trigger bars. The safety is of the cross-bolt, push-button type and located above the pistol grip. There's no separate fire mode selector on the Steyr AUG rifles. Instead, the trigger itself is used to control the mode of fire. Pulling it half the way back will produce single shots, while the full pull will produce automatic fire. The enlarged triggerguard encloses the whole hand and allows the gun to be fired in winter gloves or mittens.
The rifle features an Spz-kr type progressive trigger (pulling the trigger halfway produces semi-automatic fire, pulling the trigger all the way to the rear produces fully automatic fire) and a safety mechanism (cross-bolt, button type), located immediately above the hand grip. In its "safe" position (white dot) the trigger is mechanically disabled; pressing the safety button to the left exposes a red dot and indicates the weapon is ready to fire. Some versions have an ALO or "automatic lockout", a small projection at the base of the trigger. This was first included on the Irish Defence Forces variant of the rifle, and soon after, the Australian Defence Forces variant. In the exposed position the ALO stops the trigger being squeezed past the semi-automatic position. If needed, the ALO can be pushed up to permit automatic fire.
The AUG is categorized as a gas-operated weapon featuring an internal rotating bolt function. The gas is tapped at the barrel in the traditional sense but the gas cylinder itself is actually offset to the side of the barrel as opposed to directly over or under it (as in the AK47 or M16 respectively). As such, the cylinder doubles as a bolt guide rod during the firing operation. The AUG family is primarily chambered for the 5.56x45mm NATO cartridge (SS109/M855 NATO or M193 bullet) and fed from a standard 30-round curved detachable box magazine that is transparent, allowing the operator to visibly see his current ammunition supply. There is also a 42-round box magazine and support for a Beta C-Mag ammunition drum of 100 rounds. The submachine gun (Para) form utilizes a thinner magazine for its 9mm cartridges of 25- or 32-round counts.
Some said that the AUG rifle was revolutionary in many respects when it first appeared, but this is not true. In fact, the AUG is a clever combination of the various previously known ideas, assembled into one sound, reliable and aesthetically attractive package. Let's look at this a little closer. Bullpup configuration: The Steyr AUG is not a first military bullpup ever devised. In fact, British Enfield EM-2 and Soviet Korobov TKB-408 bullpup assault rifles precede the AUG by some 25-30 years. The French FAMAS bullpup also appeared on the scene at the very same time, as the AUG did. Plasticfirearm housing: Another Soviet experimental bullpup design, Korobov TKB-022, had the plastic housing as early as in 1962, and the FAMAS rifle, again, has this same feature at the same time as AUG did. Telescope sight as a standard: The British EM-2 bullpup rifle of late 1940s, as well as the experimental Canadian FN FAL prototypes of early 1950s, also featured a low-magnification telescope sights as their prime sighting equipment. A modular design: First systems, consisting of various firearms based on the same receiver and action (automatic rifle, light machine gun, carbine) were originally developed in 1920s in France by Rossignol and in Soviet Russia by Fedorov. Considering all said above, one must agree that the AUG was a logical development of various well known ideas,and a really successful one.
In general, the AUG is known for good ergonomics,decent accuracy and a good reliability.
Austrian variants
AUG A0:
Standard version introduced in 1978.
AUG A1:
Improved version introduced in 1982. Available with a choice of olive or black furniture.
AUG A2:
Similar to the AUG A1, but features a redesigned charging handle and a detachable telescopic sight which can be replaced with a MIL-STD-1913 rail. Introduced in December 1997.
AUG A3:
Similar to the AUG A2, but features a MIL-STD-1913 rail on top of the receiver, and an external bolt release.
AUG A3 SF (also known as the AUG A2 Commando):
Similar to the AUG A2, but features MIL-STD-1913 rails mounted on the telescopic sight and on the right side of the receiver, and includes an external bolt release. It was adopted by the Austrian Special Forces in late 2007. The sight is offered in 1.5x or 3x magnification.
AUG A3 SA USA:
Semi-automatic AUG A3 with a 407 mm (16.0 in) barrel, made available for the U.S. civilian market in April 2009.
AUG P:
Semi-automatic AUG A1 with a shorter, 407 mm (16.0 in) barrel and a modified bolt, carrier and trigger assembly that will only allow semi-automatic fire. The rifle also has a slightly different optical sight that features a reticule with a fine dot in the center of the aiming circle, allowing for more precise aiming.
AUG P Special Receiver:
Similar to the AUG P, but features a MIL-STD-1913 rail on top of the receiver.
AUG Para (also known as the AUG SMG or AUG 9mm):
Chambered in 9×19mm Parabellum and produced since 1988. Differs from A1 model in barrel, bolt, magazine and a magazine well adapter, which allows the rifle to feed from Steyr MPi 69 magazines. It is an automatic, blowback-operated model that fires from a closed bolt. Unlike the rifle variants, this SMG has a unique 420 mm (16.5 in) barrel with six right-hand grooves at a 250 mm (1:9.8 in) rifling twist rate, ended with a recoil compensator, a slightly different charging handle and a magazine well conversion insert enabling the use of standard 25-round box magazines from the Steyr MPi 81 and TMP submachine guns. A conversion kit used to transform any rifle variant into the submachine gun is also available. It consists of a barrel, bolt, adapter insert and magazine.For some time a kit of the above components was available to convert any AUG into a 9 mm variant.
AUG A3 Para XS:
9mm version of the AUG A3, similar to the AUG Para. Features a 325 mm (12.8 in) barrel and Picatinny rail system.
AUG M203:
An AUG modified for use with the M203 grenade launcher.
AUG LSW (Light Support Weapon):
A family of light support versions of the AUG.
AUG HBAR (Heavy-Barreled Automatic Rifle):
A longer, heavier-barreled version for use as a light machine gun or Squad Automatic Weapon. This version utilizes a 35 inch barrel assembly and operates with a "heavy barrel" (hence the designation) and a bipod for stabilization in the sustained fire role. The AUG Para submachine gun fires from a 16.5 inch length barrel.
AUG LMG (Light machine gun):
Based on the AUG HBAR, fires from an open bolt to allow sustained fire, has 4x rather than 1.5× optic of the base AUG.
AUG LMG–T:
Same as LMG, but has rail similar to the AUG P Special Receiver.
AUG HBAR–T:
A designated marksman rifle based on the HBAR with a universal scope mount cast into the receiver and fitted with a Kahles ZF69 6×42 optical sight.
AUG Z:
Semi-automatic version, somewhat similar to the A2, intended primarily for civilian use.
AUG SA:
Semi-automatic version of the A1 variant; built for civilian use and import to the US before being banned from importation in 1989.
USR:
An AUG A2 modified to meet the former Federal Assault Weapons Ban (AWB) (or Public Safety and Recreational Firearms Use Protection Act) regulations. The primary difference is the omission of the flash hider.
AUG A3 SA NATO:
Uses a right-hand-only, NATO STANAG magazine stock assembly.
AUG A3 M1:
Semi-automatic version, somewhat similar to the A3 SF but with a detachable optical sight which can be replaced with MIL-STD-1913 rails, manufactured in the US by Steyr Arms since October 2014.
Australian variants
F88 Austeyr:
The Australian Army's modified version of the Steyr AUG A1. Changes for the Australian version include a bayonet lug, a 1:7 in rifling pitch as found in the M16A2 rifle, optimised for the heavier 62-grain NATO-standard SS109/M855 round and an "automatic lockout" selector that can physically disable the fully automatic position of the two-stage trigger mechanism found on the standard AUG. Both the Australian & New Zealand issued F88 Austeyr incorporate a cross hair donut sight. The F88 won a competition against the prototype of what would become the Bushmaster M17S. The components are built under licence at the Thales Lithgow Small Arms Factory.
F88C Austeyr:
A carbine version of the Austeyr F88 featuring a shorter, 407 mm (16.0 in) barrel. The F88C is generally used as a personal defensive weapon where manoeuvrability is an issue, such as in armoured vehicles.
F88S-A1 Austeyr:
A version of the Australian Austeyr F88 with an integrated Picatinny rail in place of the standard optical sight that allows the attachment of various other sighting devices (night vision scopes, magnified and non-magnified optics such as the ELCAN C79, Trijicon ACOG or Aimpoint).
F88S-A1C:
The Austeyr F88S-A1C is a compact variant of the F88 fitted with a Picatinny rail. The rifle has a 407 mm (16.0 in) barrel. Typically issued to front-line combat infantry units with room and weight constraints such as cavalry, Military Police, reconnaissance, light horse, paratroopers and airfield defence guards (RAAF).
F88 GLA:
Australian Army version with an M203 grenade launcher. It features an Inter-bar (armourer attached) interface, an RM Equipment M203PI grenade launcher, and a Knight's Armament quadrant sight assembly to which a Firepoint red dot sight is attached. The bayonet lug and forward vertical grip are not present in this model.
F88T:
ADI has developed a .22-calibre training rifle for use by the Australian Army. The rifle provides an economical training alternative, with very low ammunition cost, which can be used in environmentally sensitive training areas and ranges where "overshooting" is an issue, and there is a lower risk of injuring instructors and other persons.
F88S-A2:
An evolutionary upgrade of the current rifle to fulfil an operational capability gap. Deliveries of several thousand were completed in late-2009 to selected units for overseas service. (Afghanistan) Technical improvements in the F88SA2 include: Modified gas system for increased reliability and increased interoperability with U.S ammo. An enlarged ejection port. A longer Picatinny Rail on top of the weapon, a modified sight housing, a side rail mount for a torch and Night Aiming Device (NAD). Colour of the barrel, sight and barrel assembly has been changed to khaki to reduce the recognition signature.
DSTO Advanced Individual Combat Weapon: Experimental weapon combining the barrel, action and magazine of an Austeyr F88 with an enlarged receiver and stock/body that also incorporates a multiple-shot 40 mm grenade launcher.
Enhanced F88 Austeyr: Part of the LAND 125 Soldier Combat System project, the EF88 is a significant upgrade to the F88-A2. Final design and testing is expected to end in 2013. Upgrades include the following:
1. Longer top rail and introduction of side and bottom rails.
2. Length of Pull has been shortened by 15mm.
3. Modular Lower Forend.
4. Floating Barrel – increases accuracy.
5. Fluted Barrel – dissipates heat from automatic fire.
6. Folding Cocking Handle.
7. Improved Butt design – increased strength, ejection port cover recessed to improve reliability.
8. Provision for Electronic Architecture – to allow centralised control and power management of ancillary devices.
9. Bolt-together Butt – for easier disassembly.
10. Improved Grenade Launcher Mount – improves balance of the weapon.
11. Side-Loading Grenade Launcher (Steyr-Mannlicher SL40) – can fire all currently available 40mm low velocity grenades
12. Improved Grenade Launcher safety. The KORD RIC (Rifle Input Control) is Thales new electronic control system, and will also be integrated into the rifle.
F90:
The intended for export version of the EF88, Thales debuted the F90 at the Eurosatory military exhibition in Paris, June 2012. Key additions include a bottom rail and a detachable side rail, optional compatibility with STANAG magazines, weight savings over the F88SA2 with a base weight of 3.25 kg (7 lb) and the large trigger guard has been reshaped to serve as a vertical foregrip. Thales in partnership with Steyr-Mannlicher are pursuing small arms procurement programs such as the planned replacement of FAMAS rifle used by the French military. F90 variants include Grenadier, Marksman (508 mm (20 in) barrel) and Close Quarters Battle (360 mm (14 in) barrel). Low Rate Initial Production of the F90 began in September 2014.
AUG clones
MSAR STG-556:
Introduced at the 2007 SHOT Show, the MSAR STG-556 was manufactured by Microtech Small Arms Research Inc. (a subsidiary of Microtech Knives) a AUG A1 clone significantly re-engineered in its working system and principle as it features a bolt hold-open device as seen on the M16 rifle; otherwise the MSAR STG-556 retains the original AUG features, such as feeding from proprietary translucent plastic magazines and having the quick-change barrel option. The STG-556 rifle can be converted from either having a telescopic sight or a MIL-STD-1913 rail. It is available in either civilian (semi-automatic only) and military/law enforcement (selective fire) variants.
TPD USA AXR:
Revealed at the 2007 SHOT Show, manufactured by Tactical Products Design Inc. as an AUG A2 clone capable of semi-automatic only fire, aimed for both the civilian and law enforcement markets, and fed by STANAG magazines; the manufacturer sells clear plastic magazines which are STANAG 4179 compliant and will readily fit in any rifle with a compatible magazine catch. The rifle does not have the integral scope, allowing users to use any kind of scopes or laser sights on the Picatinny railing.
Type 68:
Taiwanese copy of the AUG with notable differences including a smaller trigger guard and the use of iron sights instead of the original's telescopic sight, but it ultimately did not enter service.
Specifications
Weight
3.6 kg (7.9 lb) (Standard)
3.3 kg (7.3 lb) (Carbine)
3.2 kg (7.1 lb) (Subcarbine)
3.9 kg (8.6 lb) (HBAR)
3.3 kg (7.3 lb) (Para)
Length
790 mm (31.1 in) (Standard)
690 mm (27.2 in) (Carbine)
630 mm (24.8 in) (Subcarbine)
900 mm (35.4 in) (HBAR)
665 mm (26.2 in) (Para)
Barrel length
508 mm (20.0 in) (Standard)
407 mm (16.0 in) (Carbine)
350 mm (13.8 in) (Subcarbine)
621 mm (24.4 in) (HBAR)
420 mm (16.5 in) (Para)
Cartridge
5.56×45mm NATO
9×19mm Parabellum
Action Gas-operated, rotating bolt
Rate of fire 680–750 rounds/min
Muzzle velocity Standard rifle: 970 m/s (3,182 ft/s)