PIAT The Projector , Infantry , Anti Tank ( PIAT ) 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 , that launched a bomb using a powerful spring and a cartridge on the tail of the projectile . It possessed an effective range of approximately in a direct fire anti - tank role , and in an indirect fire ' house - breaking ' role . The PIAT had several advantages over other infantry anti - tank weapons of the period , which included a lack of muzzle smoke to reveal the position of the user , and an inexpensive barrel ; however , this was countered by , amongst other things , a difficulty in cocking the weapon , the bruising the user received when firing it , and problems with its penetrative power . The PIAT was first used during the Allied invasion of Sicily in 1943 , and remained in use with British and Commonwealth forces until the early 1950s . PIATs were supplied to or obtained by other nations and forces , including the Soviet Union ( through Lend Lease ) , the French resistance , the Polish Underground , and the Israeli Haganah ( which used PIATs during the 1948 Arab – Israeli War ) . Six members of the British and Commonwealth armed forces received Victoria Cross es for their use of the PIAT in combat . Development . At the beginning of the Second World War , the British Army possessed two primary anti - tank weapons for its infantry : the Boys anti - tank rifle and the No . 68 AT Rifle Grenade . However , neither of these were particularly effective as anti - tank weapons . The No . 68 anti - tank grenade was designed to be fired from a discharger fitted onto the muzzle of an infantryman ' s rifle , but this meant that the grenade was too light to deal significant damage , resulting in it rarely being used in action . The Boys was also inadequate in the anti - tank role . It was heavy , which meant that it was difficult for infantry to handle effectively , and was outdated ; by 1940 it was only effective at short ranges , and then only against armoured cars and light tank s . In November 1941 during Operation Crusader , part of the North African Campaign , staff officers of the British Eighth Army were unable to find even a single example of the Boys knocking out a German tank . Due to these limitations , a new infantry anti - tank weapon was required , and this ultimately came in the form of the Projector , Infantry , Anti - Tank , commonly abbreviated to PIAT . The origins of the PIAT can be traced back as far as 1888 , when an American engineer by the name of Charles Edward Munroe was experimenting with guncotton ; he discovered that the explosive would yield a great deal more damage if there were a recess in it facing the target . Known as the ' Munroe effect ' , this was developed upon further by the German scientist Egon Neumann , who found that lining the recess with metal enhanced the damage dealt even more . By the 1930s Henry Mohaupt , a Swiss engineer , had developed this technology even further and created hollow charge ammunition . This consisted of a recessed metal cone placed into an explosive warhead ; when the warhead hit its target , the explosive detonated and turned the cone into an extremely high - speed spike . The speed of the spike , and the immense pressure it caused on impact , allowed it to create a small hole in armour plating and send a large pressure wave and large amounts of fragments into the interior of the target . It was this technology that was utilized in the No . 68 anti - tank grenade . Although the technology existed , it remained for British designers to develop a system that could deliver hollow - charge ammunition in a larger size and with a greater range than that possessed by the No . 68 . At the same time that Mohaupt was developing hollow - charge ammunition , Lieutenant Colonel Stewart Blacker of the Royal Artillery was investigating the possibility of developing a lightweight 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 . By effectively putting the barrel on the inside of the weapon , the barrel diameter was no longer a limitation on the warhead size . Blacker eventually designed a lightweight mortar that he named the ' Arbalest ' and submitted it to the War Office , but it was turned down in favour of a Spanish design . Undeterred , however , Blacker continued with his experiments and decided to try and 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 come up with the Blacker Bombard , a swivelling spigot - style system that could launch a bomb approximately ; 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 . When Blacker became aware of the existence of hollow - 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 . Blacker then developed a hollow - 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 away . Blacker called the weapon the ' Baby Bombard ' , and presented it to the War Office in 1941 . 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 . 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 guerilla and resistance groups in Occupied Europe . 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 . Jefferis took the prototype Baby Bombard apart on the floor of his office in MD1 and rebuilt it , and then combined it with a hollow - charge mortar bomb to create what he called the ' Jefferis Shoulder Gun ' . Jefferis then had a small number of prototype armour - piercing HEAT rounds made , and took the weapon to be tested at the Small Arms School at Bisley . 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 unfortunately also wounded the Warrant Officer when a piece of metal from the exploding round flew back and hit him . 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 . Production of the PIAT began at the end of August 1942 . There was disagreement over the name to be given to the new weapon . A press report in 1944 gave credit for both the PIAT and the Blacker Bombard to Jefferis . Blacker took exception to this and suggested to Jefferis that they should divide any award equally after his expenses had been deducted . The Ministry of Supply had already paid Blacker £50 , 000 for his expenses in relation to the Bombard and PIAT . Churchill himself got involved in the argument ; writing to the Secretary of State for war in January 1943 he asked " Why should the name " Jefferis shoulder gun " be changed to PIAT ? Nobody objected to the Boys rifle , although that had a rather odd ring . " Churchill supported Jefferis claims , but he did not get his way . For his part Blacker received £25 , 000 ( equivalent to £ in ) . from the Inventions Board . Design . The PIAT was long and weighed , with an effective direct fire range of approximately and a maximum indirect fire range of . It could be carried and operated by one man , but was usually assigned to a two - man team , the second man acting as an ammunition carrier and loader . The PIAT launcher was a tube constructed out of thin sheets of steel , and contained the trigger mechanism and firing spring . At the front of the launcher was a small trough in which the bomb was placed , and the spigot ran down the middle of the launcher and into the trough . Padding for the user ' s shoulder was fitted to the other end of the launcher , and rudimentary aperture sights were fitted on top for aiming ; the bombs launched by the PIAT possessed hollow tubular tails , into which a small propellant cartridge was inserted , and hollow - charge warheads . To fire the weapon the trigger mechanism , which was essentially just a large spring , had to be cocked , and to do this was an extremely difficult process . The user had to first place the PIAT on its butt , then place two feet on the shoulder padding and turn the weapon to unlock the body and simultaneously lock the firing pin to the butt ; the user would then have to bend over and pull the body of the weapon upwards , thereby pulling the spring back until it attached to the trigger and cocking the weapon . Once this was achieved , the body was then lowered and turned to reattach it to the rest of the weapon , and the PIAT could then be fired . Users of a small stature often found this difficult to achieve , as they did not have the sufficient height required to pull the body up far enough to cock the weapon ; it was also difficult to do when lying in a prone position , as was often the case when using the weapon in action . When the trigger was pulled , the spring pushed the firing pin forwards into the bomb , which ignited the propellant in the bomb and launched it out of the trough and into the air . The recoil caused by the detonation of the propellant then blew the firing pin backwards onto the spring ; this automatically cocked the weapon so it could be fired . Training for using the PIAT emphasized that it was best utilized from a slit trench with surprise and concealment on the side of the PIAT team , and where possible enemy armoured vehicles should be engaged from the flank or rear . It was possible to use the PIAT as a crude mortar by placing the shoulder pad of the weapon on the ground and supporting it with a monopod , giving the weapon an approximate range of . The PIAT was often also used in combat to knock out enemy positions located in houses and bunkers . Despite the difficulties in cocking and firing the weapon , it did have several advantages ; its barrel did not have to be replaced or require high - grade materials that were expensive to produce , there was little muzzle blast that could give the user ' s position away , and the size of the barrel meant it could accommodate relatively large calibre munitions . However , the weapon did have drawbacks . It was very heavy and bulky , which meant that it was quite unpopular with the British and Commonwealth troops who were issued with it . There were also problems with its penetrative power ; although the PIAT was theoretically able to penetrate approximately of armour , field experience during the Allied invasion of Sicily , which was substantiated by trials conducted during 1944 , confirmed otherwise . During these trials , a skilled user was unable to hit a target more than 60 % of the time at , and faulty fuses meant that only 75 % of the bombs fired detonated on - target . Operational history . The PIAT entered service with British and Commonwealth units in mid - 1943 , and was first used in action by Canadian troops during the Allied invasion of Sicily . The 1944 war establishment for a British platoon , which contained 36 men , had a single PIAT attached to the platoon headquarters , alongside a mortar detachment . Three PIATs were issued to every company at the headquarters level for issuing at the CO discretion - allowing one weapon for each platoon . British Army and Royal Marines commandos were also issued with PIATs and used them in action . The Australian Army allocated a PIAT ( which was also known as Projector Infantry Tank Attack in Australian service ) to each infantry platoon in its ' jungle division s ' , which differed from the standard British organisation , from late 1943 . A contemporary ( 1944 – 45 ) Canadian Army survey questioned 161 army officers , who had recently left combat , about the effectiveness of 31 different infantry weapons , in that survey the PIAT was ranked the number one most “ outstandlingly effective ” weapon , followed by the Bren gun in second place . An analysis by British staff officers of the initial period of the Normandy campaign found that 7 % of all German tanks destroyed by British forces were knocked out by PIATs , compared to 6 % by rockets fired by aircraft . However , they also found that once German tanks had been fitted with armoured skirts that detonated hollow - charge ammunition before it could penetrate the tank ' s armour , the weapon became much less effective . The PIAT was used in all theatres in which British and Commonwealth troops served , and remained in service until the early 1950s , when it was replaced by the American bazooka . The Australian Army briefly used PIATs at the start of the Korean War alongside bazookas , but quickly replaced both weapons with M20 " Super Bazookas " . As part of the Lend Lease agreement , between October 1941 and March 1946 the Soviet Union was supplied with 1 , 000 PIATs and 100 , 000 rounds of ammunition . The PIAT was also utilized by resistance groups in Occupied Europe . During the Warsaw Uprising , it was one of many weapons that Polish Underground resistance fighters used against German forces . And in occupied France , the French resistance used the PIAT in the absence of mortars or artillery . After the end of the Second World War , the Israeli Haganah used PIATs against Arab armour during the 1948 Israeli War of Independence . Six Victoria Cross es were awarded to members of the British and Commonwealth armed forces for actions using the PIAT : Users . Some of the users of the PIAT included :