The Owen gun, as a prototype 0.22 calibre sub-machine gun, was first submitted by the inventor, Mr. Evo Owen, to the Australian Army at Victoria Barracks, Sydney in July 1939, two months after the outbreak of war. He was told firmly that the Australian Army (and probably the British Army also) was not interested in a sub-machine gun and had no expectations of requiring one in the future. Owen subsequently joined the Army as a private.

The next knowledge of the gun, nearly two years later, was when Mr. V. A. Wardell, Manager of Lysaght at Port Kembla, found the gun outside his house and learned that it belonged to a local man, Owen, who was then on final leave from the Army. Wardell recognized the simplicity and possible effectiveness of such a gun and managed to have Owen transferred to the Army Invention Board through the intervention of Mr. Essington Lewis. While some members of the Board were enthusiastic about the gun, the Army maintained a negative attitude although the Government became interested. Lysaght agreed to produce a trial gun containing some additional innovations and altering it from the original drum type feed to a magazine feed using .32 calibre ammunition. This gun required further modifications to bring it to normal Army specifications, but the army seemed unable to decide on the type and bore of ammunition that may be required. As .45 ammunition was available in Australia, a new gun of this bore was built in just the 31 days of March 1941 on the initiative of Lysaght but it was to take a further five months to obtain release of ammunition and then only at the intervention of the Minister. When the ammunition was finally released it was an incorrect .455 Webley Scott cartridge and useless for trials.

Other hold-ups occurred; for example, an order was placed for the gun to be made for use with .38 rimmed ammunition as used in service revolvers, which was useless in a sub-machine gun because of its very low muzzle velocity. The Army by this time had been pressured by the Government into arranging trials and comparisons with imported sub-machine guns and a firm date September 19, 1941 had been set.

Only 23 days before these trials, the Wardell brothers, carrying out firing trials at Maribyrnong, found out that there were adequate supplies of 9 mm ammunition available and new guns using 9 mm bore were made urgently so that Lysaght entered the trials with three 9 mm, two .45 calibre and some .38 guns.

The Owen guns performed outstandingly better than the Thompson and the British Sten guns with which they were compared for performance after all guns had been immersed separately in water, in mud and showered with sand. The Owen gun was the only one that continued firing and passed each test, the Thompson gave good performance under clean conditions but not dirty and the Sten failed badly, broke down three times to become unserviceable. The good performance of the Owen resulted from the main invention, that cocking was by a rearward extension separated from the moving parts.

In spite of the good performance of the Owen, the final Army report indicated that the tests were inconclusive and undertook to redesign the gun, in the end suggesting changes that, in many cases, were technically wrong and even unworkable. All were unnecessary and served only to waste what proved to be valuable time. Again it required pressure from the Minister for the Army to have the design matters finally settled; they reverted to the original Lysaght/Owen designs only days before Japan entered the war. Even at this stage, the Ministry of Munitions had not been informed as to whether ammunition would be 9 mm or .45 calibre nor what type of propellant would be used.

Australian Academy of Technological Sciences and Engineering