Austen MK I

The Mark I Austen (from "Australian Sten") was a 9 millimeter Australian submachine gun derived from the British Sten gun developed during the Second World War. In total 19,914 Austens were produced during the war by Diecasters Ltd of Melbourne and W. T. Carmichael Ltd of Sydney.

Design and development
With the war in Europe demanding most of the available material for the British, Australia was not in a position to purchase weapons from the UK or USA and so they had to develop their own submachine guns. The British Sten submachine gun was taken as the basis for the Austen. The barrel, body (receiver) and trigger mechanism of the Mark II Sten were copied. The folding stock and bolt, with separate firing pin and telescopic cover over the return spring, were copied from the German MP40. The folding stock also included a screwdriver and a cleaning rod which both unscrewed from the tubes of the stock. The weapon also featured twin pistol style grips; the latter containing a small spare parts container inside. The weapon had a selective-fire feature permitting the shooter to fire single shots or fully automatic at 500 rounds per minute.

An interesting production feature of the Austen was that some parts were manufactured by the diecasting process. These parts were the magazine housing, part of the mechanism for the stock and the forward half of the magazine. The magazine loader was also diecast. The two firms manufacturing the Austen were specialist diecasting companies.

There was a suppressed version made for use by "Z" special forces.

An improved version, the Mark II Austen, which an accompanying dagger type bayonet which was designed to fit over the muzzle compensator was designed and produced in limited numbers. Only 200 examples of this model were produced. Further use of diecasting was used in the Mk II.

The Austen always played second fiddle to the Owen gun. This could have been due to the Owens better suitability for jungle warfare. The side mounted magazine and bolt being exposed to dirt by the cocking slot in the right hand side of the body were both hindrances in the jungle.

The Austen was made obsolete soon after the war and was not used again.