Australia’s F1 submachine gun is one of the most recognizable and yet least known of the weapons used in the Vietnam War. Selected to replace the popular World War II–era Owen submachine gun after field testing in 1963, the F1 shared some of the Owen’s characteristics: It had a simple blowback design and fired over an open bolt with a fixed firing pin. The F1 also employed its predecessor’s curved, detachable top-loading 34-round magazine.
The magazine’s location facilitated firing from the prone position, reduced jamming and ensured more rapid loading, but it also necessitated a slightly offset leaf sight that folded down into the receiver and an offset fixed foresight. The F1’s ejection port is directly under the magazine, streamlining the firing and ejection process. But an unwary shooter could suffer a painful “bite” if his hand “wandered” back to the port while shooting.
Safety features included a bracket that prevented the shooter’s hand from moving into contact with the barrel while firing. The safety catch was above the trigger and could be operated easily by the thumb. The weapon had a two-stage trigger pull—halfway back for semi-automatic and “pull and hold back” for full automatic. The F1 had a detachable wooden butt and pistol grip.
To reduce manufacturing costs, the F1 used the same butt plate and pistol grip as the Australian L1A1 self-loading rifle and could be adapted to mount the L1A1’s bayonet. The F1’s left-mounted cocking handle was in the same position as the rifle’s. The F1 had a cover that prevented dirt and debris from entering the action, but if that occurred, the shooter could latch the cocking handle to the bolt and work it back and forth to clear away any fouling.
Carried by infantry squads, Australian artillerymen and armored personnel carrier crews, the F1 was powerful, easy to maintain and almost completely “soldier proof” in ruggedness and reliability. Even though the F1 weighed more than an M16 rifle, Australian troops found its compact size and reliability a virtue in the dense Vietnamese jungle, where most of their military operations took place.
The gun, which served with equal distinction in the 1991 Gulf War, was replaced by the Austrian-built F88C Austeyr rifle beginning in 1992.
First published in Vietnam Magazine’s October 2016 issue.