Northover Projector The Projector , 2 . 5 inch — more commonly known as the Northover Projector — was an " ad hoc " anti - tank weapon used by the British Army and Home Guard during the Second World War . With a German invasion of Great Britain seeming likely after the defeat in the Battle of France , most available weaponry was diverted to the regular British Army , leaving the Home Guard short on supplies , particularly anti - tank weaponry . The Northover Projector was designed by a Home Guard officer named Robert Harry Northover to act as a makeshift anti tank weapon , and was put into production in 1940 following a demonstration to the Prime Minister , Winston Churchill . The weapon consisted of a hollow metal tube attached to a tripod , with a rudimentary breech at one end . Rounds were fired with the use of black powder ignited by a standard musket percussion cap , and it had an effective range of between 100 and 150 yards . Although it was cheap and easy to manufacture , it did have several problems ; it was difficult to move and the No . 76 Special Incendiary Grenade s it used as one type of ammunition had a tendency to break inside the breech , damaging the weapon and injuring the crew . Production began in late 1940 , and by the beginning of 1943 nearly 19 , 000 were in service . Like many obsolete Home Guard weapons , it was eventually replaced by other weapons , such as the 2 - pounder anti tank gun . Development . With the end of the Battle of France and the evacuation of the British Expeditionary Force from the port of Dunkirk between 26 May and 4 June 1940 , a German invasion of Great Britain seemed likely . However , the British Army was not well - equipped to defend the country in such an event ; in the weeks after the Dunkirk evacuation it could only field twenty - seven divisions . The Army was particularly short of anti - tank guns , 840 of which had been left behind in France , leaving only 167 available in Britain ; ammunition was so scarce for the remaining guns that regulations forbade even a single round being used for training purposes . Given these shortcomings , any modern weapons that were available were allocated to the British Army , and the Home Guard was forced to supplement the meagre amount of outdated weapons and ammunition they had with " ad hoc " weapons . One such weapon was the Northover Projector , the invention of Major Robert Harry Northover . Northover , an officer in the Home Guard , designed it to be an easily manufactured and cheap anti - tank weapon , costing just under £10 to produce , excluding the required tripod . The Major wrote directly to the Prime Minister , Winston Churchill , with his design and arranged for Churchill to attend a demonstration of the Northover Projector . The Prime Minister approved of the weapon and gave it his personal endorsement , ordering in October 1940 that the weapon be mass - produced on a scale of one for every Home Guard platoon . Design . The Northover Projector — which was officially labelled the " Projector , 2 . 5 inch " by the War Office — was formed of a hollow metal tube , resembling a drain pipe , mounted on top of a cast - iron tripod . It weighed approximately 27 . 2 kilograms . A simple breech was attached to one end of the tube , and rounds were fired from the Projector with a small quantity of black powder detonated by the cap from a toy pistol ; any recoil from the weapon was absorbed by the legs of the tripod , which were also hollow . It had a maximum range of approximately 300 yards but was only accurate to between 100 and 150 yards Home Guard units often added their own modifications to the weapon , which included mounting it on carriages or even the sidecars of motorcycles . It was served by a crew of three . Ammunition for the weapon consisted of the No . 76 Special Incendiary Grenade , a glass bottle " containing a phosphorus mixture which burst into livid flames , giving off quantities of suffocating smoke upon exposure to the air " , as well as normal hand and rifle grenades . The Projector had a number of defects . It was difficult to move , the tripod had the tendency to damage itself if it was dropped , and its discharge pressure has been described as " feeble . " The phosphorus grenades exhibited a number of faults when used in the Projector ; they could often explode inside the weapon if too much black powder were added , or fall short if too little were used , or even fail to explode . They could also break inside the barrel when fired which often led to the weapon being damaged and its crew injured . Even when fired properly , the Projector gave off a large cloud of smoke which could take up to a minute to clear and revealed the weapon ' s position . Bishop argues that its anti - tank abilities would have been ' doubtful ' when it fired hand and rifle grenades , although he considers that the phosphorus grenades might have been more successful . To make handling easier , a lighter version of the weapon , the Northover Projector Mk 2 was developed in 1941 , but few were produced . Operational history . The Northover Projector was issued to both Home Guard and regular British Army units , and by August , 1941 over 8 , 000 Northover Projectors were in service . This number had increased to 18 , 919 by the beginning of 1943 . Initial reactions to the Northover Projector were varied , with a number of Home Guard volunteers uncertain about the weapon ' s unusual design , and some officers never accepted that it could be useful . However , most Home Guard units came to accept the weapon and have confidence in it , aided by large amounts of what Mackenzie terms " War Office propaganda " which cited the positive qualities of the weapon , such as its simplicity of use , ease of manufacture and low maintenance requirements . It was , as one Home Guard volunteer put it , " something to be accepted gratefully until something better arrived . " Like many of the obsolete weapons designed for the Home Guard , the Northover Projector was only taken out of service when it could be replaced with " marginally less ineffective " weapons provided by the Army , such as the 2 - pounder anti tank gun .