The retreat to Dunkirk, in May 1940, had proved to the British Army that it was equipped to fight a war that had ended 20 years earlier. Anti-Tank weaponry of any kind was very poor and the principle armament of the infantry at the time, the Boys anti-tank rifle, could only penetrate light armour and as such was wholly ineffective against the modern German Panzers, which were at liberty to break through the Allied lines at will.
Rocket-propelled anti-tank weaponry was still in their infancy at this stage in the war and so the several earmarked replacements were based on the design of the spigot mortar, a simple projectile weapon. The retired Lieutenant-Colonel Blacker had, prior to the war, specialised in inventing a range of inexpensive home-made weaponry in his work shop, amongst which was the large "Blacker Bombard" spigot mortar. With a view to making a single-handed variant for the infantry, he turned his attention towards designing the "Baby Bombard". Major Jefferis took over the design when Blacker was posted to other duties, and so emerged the Jefferis Shoulder Gun.
The weapon was so simple in its design and so crudely constructed that at a glance it appeared to be amongst the very worst of amateurish efforts. Its main component was a cylindrical steel tube housing a powerful spring, at the end of which was a spigot and a trough, into which one placed a high-explosive projectile, and this was fired by pulling an almost comically large trigger. It was a most unlikely weapon and initial trials were not promising when the projectile struggled to make much of an impression upon armoured targets, however it was found that by shaping the tip of the bomb into a long point its effectiveness was considerably improved.
Towards the end of 1942, the War Office took on board the design and christened it the PIAT (Projector Infantry Anti-Tank). It became the undisputed anti-tank weapon of the British infantryman during the Second World War, and by 1945 a total of 115,000 were in circulation.
The PIAT entered service during 1943 and was first used by Canadian troops in Sicily. Its debut performance was not a happy one due to a fault in the bomb which misfired if it struck a target from any position other than square-on, and as a result the confidence of soldiers in the PIAT was greatly undermined. There followed a considerable effort to remedy the problem and restore the Army's faith before the weapon was used on French soil. Even so the bomb remained, throughout the war, considerably volatile due to the premature detonation of fuses. Such was the extent of the problem that live firing exercises were banned when the war came to an end.
In spite of its unlikely appearance, the PIAT was amongst the most effective infantry anti-tank weapons of its day, with a performance equal to that of the visually more sophisticated American bazooka. Although it was a cumbersome device, it possessed a number of advantages over such rocket weapons, namely that there was no back-blast from firing, and so not only could it be safely fired from an enclosed space, but it would also not give away its handlers position to the enemy. The PIAT could also be used as a makeshift mortar, by rotating the T-shaped shoulder stock through 90 degrees and wedging the weapon into any solid foundation, such as a tree or a wall.
The range of the PIAT was, however, very short. It was effective against large targets, such as buildings, at 350 yards, but it was only truly effective against armour at a range of 100 yards, although many operators preferred their target to be closer still. The PIAT bomb could penetrate 75mm of armour plate and so was ideally suited to dealing with light or medium armoured targets, however given the right conditions it was capable of dispatching any tank in service.
Despite its effectiveness, the PIAT could be a brute to handle and it was not the soldier's best friend. It was heavy and awkward to carry, and commonly two soldiers were needed for its use: one to carry the weapon, the other the ammunition. The mechanism was not easy to load, although once cocked for a first time it was designed so that the recoil would, in theory but not always in practice, reload the spring automatically. With a 90kg draw, reloading required both strength and the acquired skill. Although it was relatively easy to prime whilst in a standing position, this was not often practical under battle conditions, yet it was possible, albeit difficult, to cock it whilst lying down. The trigger required at least two fingers to pull and there was always a slight delay in firing, during which time an inexperienced operator might not hold the trigger back long enough, causing the spring reload to fail, not to mention the weight of the recoil being redirected into their shoulder, leaving it stunned. Also there was a 12lb shift in weight towards the front of the PIAT a tenth of a second before the round was released, thus the operator had to be ready to counter this effect.
Following the end of the war, technology in other methods of anti-tank weaponry were improved and the PIAT soon become obsolete, however it did experience a swansong during the Korean War before being finally retired from service in 1951.
Manufacturer : ICI Ltd., various others.
Overall Length : 990mm or 39"
Weight : 31.7 lbs or 14.4kg
Projectile Weight : 3lb or 1.35 kg
Muzzle Velocity : 137 m/s or 450 ft/s
Effective Range : 100 m or 109 yards