Louis, a response to your comment on the K&C thread about the PIAT.
Recommend ref:
https://en.wikipedia.org/wiki/PIAT
The
Projector, Infantry, Anti Tank (
PIAT) Mk I was a British man-portable
anti-tank weapon developed during the
Second World War. The PIAT was designed in 1942 in response to the
British Army's need for a more effective infantry anti-tank weapon and entered service in 1943.
The PIAT was based on the
spigot mortar system, and projected (launched) a 2.5 pound (1.1 kg)
shaped charge bomb using a cartridge in the tail of the projectile.
[5]
It possessed an effective range of approximately 115 yards (105 m)
[3] in a
direct fire anti-tank role, and 350 yards (320 m)
[3] in an
indirect fire role.
The PIAT had several advantages over other infantry anti-tank weapons of the period: it had greatly increased penetration power over the previous anti-tank rifles, it had no back-blast which might reveal the position of the user or accidentally injure friendly soldiers around the user, and it was simple in construction.
However, the device also had some disadvantages: powerful recoil, a difficulty in cocking the weapon, and early problems with ammunition reliability.
Lieutenant Colonel Stewart Blacker was developing a platoon mortar. However, rather than using the conventional system of firing the mortar shell from a barrel fixed to a baseplate, Blacker wanted to use the
spigot mortar system. Instead of a barrel, there was a steel rod known as a "spigot" fixed to a baseplate, and the bomb itself had a propellant charge inside its tail. When the mortar was to be fired, the bomb was pushed down onto the spigot, which exploded the propellant charge and blew the bomb into the air.
[10]
By effectively putting the barrel on the inside of the weapon, the barrel diameter was no longer a limitation on the warhead size.
[11]
Blacker eventually designed a lightweight mortar that he named the "Arbalest" and submitted it to the
War Office,
[12] but it was turned down in favour of a Spanish design.
Undeterred, however, Blacker continued with his experiments and decided to try to invent a hand-held anti-tank weapon based on the spigot design, but found that the spigot could not generate sufficient velocity needed to penetrate armour.
But he did not abandon the design, and eventually came up with the
Blacker Bombard, a swivelling spigot-style system that could launch a 20-pound (9 kg) bomb approximately 100 yards (90 m). Although the bombs it fired could not actually penetrate armour, they could still severely damage tanks, and in 1940 a large number of Blacker Bombards were issued to the
Home Guard as anti-tank weapons.
[13]
When Blacker became aware of the existence of shaped charge ammunition, he realized that it was exactly the kind of ammunition he was looking for to develop a hand-held anti-tank weapon, as it depended upon the energy contained within itself, and not the sheer velocity at which it was fired.
[14]
Blacker then developed a shaped charge bomb with a propellant charge in its tail, which fitted into a shoulder-fired launcher that consisted of a metal casing containing a large spring and a spigot; the bomb was placed into a trough at the front of the casing, and when the trigger was pulled the spigot rammed into the tail of the bomb and fired it out of the casing and up to approximately 140 metres (150 yd) away.
Blacker called the weapon the "Baby Bombard", and presented it to the War Office in 1941.
[14] However, when the weapon was tested it proved to have a host of problems; a War Office report of June 1941 stated that the casing was flimsy and the spigot itself did not always fire when the trigger was pulled, and none of the bombs provided exploded upon contact with the target.
[15]
At the time that he developed the Baby Bombard and sent it off the War Office, Blacker was working for a government department known as
MD1, which was given the task of developing and delivering weapons for use by guerrilla and resistance groups in Occupied Europe.
[1]
Shortly after the trial of the Baby Bombard, Blacker was posted to other duties, and left the anti-tank weapon in the hands of a colleague in the department,
Major Millis Jefferis.
[1]
Jefferis took the prototype Baby Bombard apart on the floor of his office in MD1 and rebuilt it, and then combined it with a shaped charge mortar bomb to create what he called the "Jefferis Shoulder Gun".
Jefferis then had a small number of prototype armour-piercing
high-explosive anti-tank (HEAT) rounds made, and took the weapon to be tested at the Small Arms School at
Bisley.
[16]
A
warrant officer took the Shoulder Gun down to a firing range, aimed it at an armoured target, and pulled the trigger; the Shoulder Gun pierced a hole in the target, but also wounded the warrant officer when a piece of metal from the exploding round flew back and hit him.
[16]
Jefferis himself then took the place of the warrant officer and fired off several more rounds, all of which pierced the armoured target but without wounding him.
Impressed with the weapon, the Ordnance Board of the
Small Arms School had the faults with the ammunition corrected, renamed the Shoulder Gun as the Projector, Infantry, Anti Tank, and ordered that it be issued to infantry units as a hand-held anti-tank weapon.
[17]
Production of the PIAT began at the end of August 1942.
[1]
