The STEN Mk.IV was derived from the STEN Mk.II. It was designed in 1943
especially for paratroopers. Two variants existed. The Mk.IVA had a very
large trigger guard for arctic mittens and a retractable shoulder stock.
It was 27.2 inches long, whereas the Mk.I was 35.2 inches and the Mk.II
and III were 30 inches long. It was considered uncomfortable to fire and
rejected during trials.
The Mk.IVA STEN.
The Mk.IVB was the second variant of the
STEN Mk.IV. The Mk.IVB was designed for firing with one hand; the pistol
grip was further towards the magazine and the overall balance of the
weapon was better. The trigger guard and grip were redesigned. Collapsed,
it was 24.2 inches. Both models had 3.85-inch barrels.
The Mk.IVB STEN.
A few wooden-stocked STENs were
prototyped. A STEN Mk.II with an SMLE rifle stock was prototyped,
but nothing became of it due to high production costs. A
wooden-bodied STEN Mk.III with bayonet fittings was prototyped but
never mass produced for the same reasons. Probably the most unusual
wooden STEN was a Mk.III prototype with an entirely wooden body. The
pistol grip and trigger were directly below the magazine feed and
the cocking lever was relocated to the top of the weapon. The stock
was raised. The exact reason for the creation of this STEN is
unknown, but it was probably an experiment in weapon handling and
A Mk.II STEN with an SMLE-pattern stock.
A Mk.III STEN with a Lanchester-style body and bayonet.
A Mk.III STEN with an experimental wooden body.
A special STEN Mk.II was designed
for parachutists. It was intended to be used whilst descending
with a parachute. It was very cheap to produce but not very
comfortable to fire. It was never fielded in large numbers.
A Mk.II STEN with a pistol grip.