Here are some pictures of Evelyn Owen’s homebuilt .22 submachine gun made from bits of scrap steel and .22 short rifle parts in his younger years. Some time after a test firing session at a local beach, it was discovered carelessly left against a garage wall by his neighbor, who fatefully happened to manage the Port Kembla plant of Lysaght’s Newcastle Works. Impressed with his simplistic design he arranged for him to be transferred to the Australian Army Invention Board where he began work on what would later became the Owen Machine Carbine.

The design contains a hilariously simple trigger made from a piece of spring steel which also catches the end of the bolt handle. It’s magazine is interestingly powered by a large flat coil spring. Can anyone decipher this component’s workings further? By all accounts it functioned quite well.

Edit: A commenter has spotted the magazine wheel as being made from an old harmonic balancer / crank shaft damper.

Bolt and trigger operation:

 Australian War Memorial site