The Steyr AUG has been developed since the late 1960s by the Austrian Steyr-Daimler-Puch company in conjunction with the Austrian Army. This assault rifle has been adopted in 1977 as the St G.77. It replaced the obsolete St G.58 assault rifle, which was a license-built version of the FN FAL.

Since its introduction the AUG gained serious popularity. This weapon is license produced in Australia as the Lithgow F88, commonly known as Austeyr.

The ammunition was to be APDS or APFSDS with early development concentrating on APDS.

Steyr single-81

It uses standard 25-round magazines from a Steyr TMP submachine gun.

A conversion kit is available, which is used to transform any AUG rifle variant into the submachine gun; Lithgow F88, commonly known as AUSTEYR.

It was either overlooked or ignored that the AUG contained more steel than most submachine guns.

It was also somehow forgotten that x-ray machines had no difficulty detecting non-metalic objects. There are two symmetrical ejection ports, one of which is always covered.

Pulling it half the way, will result in a single shot, while the full pull will result in full-auto fire.

The Steyr AUG is fed from box-shaped translucent polymer magazines, that hold 30 rounds.

Steyr AUG A3 the most recent version, produced since 2005.

It is fitted with four Picatinny-type rails and has no integrated sighting equipment.

Trials with these weapons resulted in a change of caliber to 15.2 mm and a change of program name to Infantry Weapon System 2000 (IWS 2000).