In this video we take a look at an original 1970s brochure for an Oerlikon 20mm Cannon. The booklet, printed in 1974, covers the Type GAI-BO1 – which had previously been designated the 10ILa/5TG. The Swiss Oerlikon had been introduced in the mid-1930s and seen widespread on both sides use during the Second World War.
Engagement of Ground Targets (Matthew Moss)
The brochure covers the anti-aircraft and ground roles the cannon was capable of fulfilling as well as explaining the major assemblies of the weapon and some of the accessories like sights and magazines. The brochure also lays out some of the ammunition available for the Oerlikon, ranging from practice shells to fragmentation HE incendiary and armour-piercing hard core shells. The Oerlikon cannon remains in production and in service with dozens of countries around the world.
Sights, mounts and ammunition (Matthew Moss)
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The need for a lightweight self-propelled anti-tank gun was identified in the late 1940s. The T101 development program took just over 5 years and $2.5 million dollars to develop what became the M56.
Front, right view of the M56 Scorpion (Matthew Moss)
The M56 was intended to act as an airmobile support weapon for the US Army’s airborne forces that was capable of traversing muddy, marshy, sandy and snowy terrain. Airborne infantry have historically been lightly armed and sometimes struggled against enemy forces equipped with armour. Attempts to level the playing field with glider transported anti-tank guns or even super light tanks could only do so much. Airborne operations during world war two proved light tanks, like the M22 Locust, were out-gunned, under-armoured and largely useless. While light artillery proved effective it lacked mobility and while infantry anti-tank weapons like the Bazooka were extremely useful they were close quarter weapons.
The T101 – Prototype M56 (US National Archive)
In response the US Army decided to abandon one of the points of the classic ‘iron triangle’ of armoured vehicle design all together, sacrificing protection for firepower and mobility. The unarmoured 16,000 lb (7 tonne) vehicle could be dropped from a transport plane to support paratroops and later heliborne air cav units.
An M56 (US Army)
The M56 was developed and manufactured by the Cadillac Motor Car Division of General Motors, a pilot version was completed by 1955. The pilot model, designated the Full-Tracked Self-Proppelled Gun T101 is seen in this photograph from October 1955. When the vehicle finally entered production in 1957 it was largely identical to the T101 except for changes to the location of the radio, the design of the gun’s muzzle device, the hinged flaps on the gun shield were abandoned and the sand skirts were also abandoned. The Scorpion had no secondary armament and no armour. Protection for its 4-man crew amounted to nothing more than a gun shield, which also has a window for the driver.
A view of the ‘fighting compartment’ of the M56, the ammunition storage rack is missing(Matthew Moss)
View of the driver’s position (Matthew Moss)
The 90mm M54 high velocity gun was mounted on a pintle in the centre of the vehicle with the driver on the left and the vehicle commander, loader and gunner sat around the gun. The gun could be traversed 30-degrees left and right and had 10-degrees depression and up to 15-degrees elevation. At the rear of the vehicle was an ammunition store that held 29 90mm rounds. The main ammunition used with the M54 would have been the M318 armour piercing round but it could chamber any of the other 90mm ammunition then in US service. Sadly the ammunition store and breech of the gun aren’t present on this example.
An M56 in action, note the ammunition storage racks (US Army)
The gun’s impressive recoil, even with a pair of recuperators, hit the Scorpion and the crew manning it hard, the footage shows just how powerful the recoil was. In this contemporary footage we can see that the front wheel almost bounces off the ground. Note also the semi-automatic action that opens the breech and ejects the spent shell casing after the gun is fired.
The vehicle was powered by an air-cooled petrol engine that produced 200hp. Capable of a maximum speed of just over 28mph.
Front, left view of the M56 (Matthew Moss)
Perhaps its most interesting feature is that it runs on four pneumatic road tyres, rather than metal road wheels, enclosed in a 20in wide track. The track was made up of two bands of rubber and steel cross pieces. There’s a sprocket at the front and an idler at the rear for tensioning the track. This configuration was chosen to reduce weight and it also minimised the ground pressure of the vehicle.
Production of the M56 ended in 1959, after around 325 had been produced. While most of these entered US service, 87 were purchased by Morocco in 1966 while a further 5 were used by the Spanish Marine Corps.
M56s in Vietnam (US Army)
While the M56 was slightly more mobile across country, in reality it wasn’t much better than a standard jeep equipped with a M40 recoilless rifle. Despite the Scorpion’s shortcomings it remained in service into the early 1970s and saw action during the Vietnam War with the 173 Airborne Brigade, which had a company of 16 M56s. In Vietnam the more capable and better protected M551 Sheridan saw wider use and what action the Scorpions did see was largely acting in direct fire support.
Special thanks to Battlefield Vegas for allowing us to film and feature their M56.
The Boeing Bomarc was the world’s first long-range surface to air missile and despite its shortcomings remain in service for a decade. It was an extremely ambitious project and is a Cold War weapon that few today are familiar with.
In the late 1940s, Boeing began work on a surface to air missile – then described as a ‘pilotless interceptor’. The project was code-named MX-1599 and the Michigan Aerospace Research Center (MARC) joined Boeing to work on the programme.
Boeing BOMARC at Hill Aerospace Museum (Matthew Moss)
The MX-1599 was to be a long-range supersonic nuclear-tipped surface to air missile (or SAM), detonated by a proximity fuse. The missile went through a number of official designations as it was developed during the 1950s – finally becoming known as the Bomarc – an acronym of Boeing and Michigan Aerospace Research Center.
The Bomarc was launched vertically using rocket boosters, before its main ramjet engines took over, enabling it to cruise at Mach 2.5 (approx. 1,920 mph). The initial Bomarc A had a range of 200 miles with an operational ceiling of 60,000 feet.
It was ground controlled using NORAD’s Semi-Automatic Ground Environment (SAGE) system until it neared its target, when an onboard radar, a Westinghouse AN/DPN-34 radar, took over.
The Bomarc could be tipped with either a 1,000 lb conventional high explosive or low yield W40 nuclear warhead. These were detonated by a radar proximity fuse. The W40 had a yield of up to 10 kilotons, able to destroy entire formations of aircraft.
BOMARC Site No. 1 at McGuire Air Force Base (USAF)
The missile had a wingspan of just over 18 feet or 5.5metres, it was 45 feet or 13.7 metres in length and weighed approximately 16,000 lbs (7257 kg) on launch. The Bomarc’s first flight took place on 24th February, 1955.
The USAF intended to use the missile to engage incoming Soviet bomber formations and ICBMs. Originally planning for over 50 Bomarc launch sites, but only one was operational by 1959 and only eight were operational by the early 1960s. The upgraded Bomarc B was developed in the early 1960s, with an improved radar, a Westinghouse AN/DPN-53, and a greater maximum range of 430 miles, as well as a higher operational ceiling of 100,000 feet.
The Bomarc was stored horizontally in specially built semi-hardened bunkers and kept fuelled and ready to launch at a moment’s notice. When targets were detected the missile would be raised and launched vertically.
One of the dangers of keeping the missiles fuelled became clear in June 1960, when a nuclear-armed Bomarc A caught fire exploding the onboard tank and contaminated part of McGuire Air Force Base with melted plutonium. Despite this the missiles remained operational for over a decade with the first sites being deactivated in 1969 with the last stood down in 1972.
BOMARC launching (USAF)
While the Bomarc missiles were the world’s first operational long-range anti-aircraft missile they were too slow to achieve operational readiness to keep pace with the rapidly changing nuclear threat – as both superpowers transitioned from bomber to ICBM-focused strategies. They were expensive to manufacture and difficult to maintain at readiness. In the late 1950s the Bomarc also embroiled in a war of words with the US Army arguing their short range Nike Hercules (SAM-A-25/MIM-14) missile was more effective. The Hercules remained in service through to the 1980s, albeit as a air defence missile – rather than targeting soviet ICBMs or bomber aircraft.
The Bomarc was an ambitious project when it began in the late 40s, but with technology and cold war nuclear strategy rapidly evolving the Bomarc was almost obsolete before it became operational. A total of 570 Bomarc missiles were built between 1957 and 1964 with the US and Canada (which led to considerable political controversy) being the only countries to deploy them.
I hope you guys enjoyed this look at the Bomarc, we’ll have a few more videos on missiles in the future.
IM-99A/B BOMARC Missile, Boeing, (source) Nuclear Weapons of the United States: An Illustrated History, J.N. Gibson, (1996) Nike Historical Society (source)
Supersonic Guardian, Boeing film, c.1960 (source)
While doing some research in the US National Archives’ online catalogue I came across a very interesting video composed of footage from a couple of US Army Ordnance demonstrations so I thought I’d take the opportunity to talk about some very big guns.
Railway guns emerged during the late 19th century as a way of moving massive, large calibre guns which had a reach far beyond that of field artillery. Before aircraft were able to effectively attack behind enemy lines railways allowed armies to bring huge guns within range and harass their enemies lines of communication and supply.
This footage comes from Ordnance demonstrations at the Aberdeen Proving Ground in the early 1920s.
16in Coastal Gun (US National Archives)
First up we have a US-built copy of the French 305mm Canon de 305 modèle 1893/96 à glissement, which according the original footage notes, was a 10in sliding mount for a gun firing a 150lb projectile. I also found some contemporary images of the gun being built at the US Watertown Arsenal, in Massachusetts, which describes it as the Model 1919. It may be the only example built by the US, Schneider built 8 of these guns for France during the war. When the gun fires we can see the whole gun and carriage recoil back a meter or so. Guns on sliding mounts cant be traversed and have to be aimed with specially laid track.
Next we have a 12 inch M1895 gun, mounted on a M1918 railway carriage which was based on the French Batignolles mount, with 360-degree traverse. Originally designed as a coastal defence gun, here’s a photograph taken in 1918 of the gun firing from a disappearing mount.
The M1895 had long been used as a coastal defence gun, and with US entry into the war surplus or unnecessary coastal guns were remounted as railway guns. The railway mounted M1895s had a large recuperator to mitigate the gun’s recoil. 12 were mounted, however, none reached France before the end of the war. We also get a nice shot of the shell hitting its target in the distance.
The 14 inch railway guns were the only big US guns to see action during WW1. Taking spare US Navy 14in naval guns, the 14″/50 caliber Mk 4 gun, which had been mounted in the New Mexico and Tennessee-class battleships, and mounting them in a carriage built by the Baldwin Locomotive Works. Once in position the guns had to have a recoil pit dug out beneath the carriage to allow space for the gun to recoil when it was at high elevation. They had a range of up to 25 miles.
Five Mk1 guns made it to France operating as single gun batteries manned by US Navy Sailors. The guns fired a total of 782 shells during the war, with Battery 4 firing its last shell at 10:57:30 a.m. on 11 November 1918.
Unlike the MkI guns that made it to France in this footage we see the gun without an armoured gun house, with the gunners working the gun in the open.
An M1919 16in Coastal Gun in a Barbette mount (US National Archives)
Finally, we have the truly massive 16 inch M1919 coastal gun . Designed for the Army Coast Artillery Corps to defend the US’ major coastal ports the 16-inch gun could throw a 2,340 lb shell up to 28 miles. In this footage we can see the gun mounted on an M1919 barbette carriage which could be elevated up to 65-degrees.
This second piece of footage dates from between 1929 and 1931, with dozens of West Point cadets gathered eagerly to see the gun in action.
Demonstration of Ordnance Materiel at Aberdeen Proving Grounds, 1920-1926 (source)
Railway Artillery: A Report on the Characteristics, Scope of Utility, Etc., of Railway Artillery, Vo.1, H.W. Miller & US Ordnance Dept. (1921) (source)
Railway Artillery: A Report on the Characteristics, Scope of Utility, Etc., of Railway Artillery Vol.2, H.W. Miller & US Ordnance Dept. (1922) (source)
The United States Naval Railway Batteries in France, E. Breck (1922) (source)
Development of the gun actually began before the war in 1938, but the QF 6pdr MkII Anti-Tank gun didn’t enter full production until 1942. After the evacuation from Dunkirk in the summer of 1940, and the loss of nearly 600 AT guns, it was decided to focus on the 2pdr which was then already in production. The 6pdr saw action for the first time in the Western Desert against the Afrika Korps, serving alongside its predecessor the 2pdr.
QF 6pdr AT Gun (Matthew Moss)
The 6pdr was a 57mm gun, firing a 57x441mmR shell effective out to 1,700 yards or 1,500m – with a rated maximum range of 5,000 yd. Unlike its predecessor the 6pdr could fire both armour piercing and high explosive rounds. The gun weighed in at 2,520 lb or just under 1,150 kg. Manned by a six man crew the gun had a vertically sliding breechblock and could fire up to 15 rounds per minute.
Breech View of the QF 6pdr (Matthew Moss)
The 6pdr had a Hydro-pneumatic recuperator which mitigated some of the gun’s recoil. The barrel recoiled around 30 inches along its cradle immediately after firing. It was mounted on a variety of carriages with the most common being a split trail carriage with 45-degrees of traverse left and right. The 6pdr could be fired with its split trail deployed or closed. The gun could be elevated 15-degrees and depressed 5-degrees – less than its predecessor, although elevation was not a key requirement for a direct fire weapon like an anti-tank gun.
Five Marks of 6pdr were produced, the MkI development model was declared obsolete and didn’t enter production. Production of the MkII began in late 1941, it had a shorter barrel and was later replaced by the longer barrelled MkIV, which also had a single-baffle muzzle brake, one of the first British guns to have one. The MkIII and V variants had special lugs to enable them to be mounted in tanks. The first guns produced were MkIIIs, while these could be carriage mounted they were earmarked for tanks.
Airborne troops with a 6-pdr anti-tank gun in Hamminkeln, March 1945 (IWM)
The MkIII Airborne carriage was designed to be lighter so it could be transported aboard gliders and aircraft. Its trail legs were jointed in order to save room and the carriage was narrower which restricted the traverse to 37-degrees left or right. The shield was also redesigned with an even smaller profile. Identifiable by its straight, rather than wavy, top edge.
The gun was aimed using a No.22C 2 or 3-power sighting telescope, located on the left side of the gun, which projected through a sight box in the shield. The gunner also had an elevation wheel to his right and, unlike the 2pdr, the 6pdr used a free traverse rather than a geared wheel system. This was controlled by the gunner pushing or pulling the gun. The gun was fired by a firing lever on the left side of the breech. On the right side of the gun, an ammunition box with space for three rounds could be attached to the shield for emergency use. The gun shield consisted of two/four sections, made of bulletproof steel plate, which had a lower profile than the earlier 2pdr.
A New Zealand 6-pdr anti-tank gun in action against enemy positions at Cassino, March 1944 (IWM)
Unlike the 2pdr, the 6pdr had an array of ammunition that continued to evolve during the war. The initial armour piercing round could penetrate 70mm or 2.8in of armour at 1,600 yards / 1,500m while the Armour-Piercing Capped Ballistic Cap (APCBC) introduced in early 1943 increased this to 3.1in, while the Armour-Piercing, Discarding Sabot (APDS) shot introduced in Spring 1944, enabled it to effectively engage Tiger I and Panther frontal armour, penetrating 4.8 inches of armour at 1,500m. It is worth noting that figures on penetration vary somewhat from source to source. A high explosive shell that allowed the guns to engage non-armoured targets more effectively was introduced in 1943.
Initially used solely by the Royal Artillery’s anti-tank regiments comprising of four batteries, each with 12 guns. By 1944 an infantry division would be equipped with as many as 78 6pdrs and more than 30 heavier 17pdrs while an armoured divisions was equipped with 30 6pdrs.
British 6pdr anti-tank gun in action in the desert, 3 September 1942 (IWM)
The 6pdrs first saw action in North Africa proving to be highly effective against both Italian and German armour. During the Second Battle of El Alamein, 19 6pdrs were instrumental in the defence of Outpost Snipe. The 2nd Rifle Brigade and their supporting 6pdrs managed to knock out more than 55 Axis armoured vehicles including Panzer IIIs, Semovente 75/18 self-propelled guns and a number of Panzer IVs. The gunners used enfilading fire to target weaker side armour and interlocked fields of fire caught advancing tanks in killing grounds.
During Operation Market Garden, the airborne 6pdrs of the Airlanding Anti-Tank Batteries proved critical in beating back German armoured counter attacks around Oosterbeek and at the bridge in Arnhem itself. They were instrumental in repulsing the SS reconnaissance battalion which attempted to cross the bridge on the second day of the battle.
One desperate action involving a section of two 6pdrs saw three StuG-III self-propelled guns knocked out before the crews of both guns were killed. The last survivor, Lance-Sergeant Baskeyfield managed to man on of the guns alone and destroy a fourth StuG-III before he was killed. For his actions he was awarded the Victoria Cross.
Churchill MkIII tanks armed with QF 6pdrs, North Africa, 1942 (IWM)
Like its predecessor the 6pdr was also used as a vehicle gun, mounted in the Churchill Mks III & IV, Valentine Mk IX and the Crusader Mk III tanks as well as the Canadian MkII Ram and the MkII AEC Armoured Car. These vehicles had previously been designed to mount the 2pdr, but were adapted to fit the new 6pdr, in some cases having to remove a crew member from the turret to make enough room to fit the new gun. The Cavalier, Cromwell and Centaur tanks were designed to mount the new larger gun from scratch.
The first tank, equipped with a 6pdr, to go into action was the Mk III Churchill, which took part in the disastrous Dieppe Raid in August 1942. The new tanks, assigned to the 14th Army Tank Regiment (The Calgary Regiment (Tank)), were all abandoned or destroyed during the raid.
In North Africa, like the 2pdr, the heavier guns were mounted on trucks as Portees. Additionally AEC produced the Mk1 Gun Carrier or Deacon self-propelled gun – a 6pdr mounted in an armoured turret on the back of an AEC Matador truck chassis. These performed well in the desert but more enclosed country made them vulnerable and they were removed from service after the North African campaign.
A truck mounted 6-pdr anti-tank gun (Portee) in the Western Desert, 31 May 1942 (IWM)
It was not only tanks the 6pdr found itself mounted in. Coupled with the Molins automatic loading system it was also mounted in the RAF’s De Havilland Mosquito Mark XVIII ‘Tstetse’ and the Royal Navy’s motor torpedo boats. The Navy’s Molins auto-loader allowed the gun to fire a 6-round burst at a rate of 1 round per second. Nearly 600 naval versions of the gun, the QF 6pdr MkIIA, were produced. The RAF’s use was more short-lived with only 17 6pdr Tstetses built before 3in rockets were standardised. Despite this two Tsetse of 248 Squadron sank the German submarine U-976 in March 1944.
The US also adopted the 6pdr to replace their 37mm M3 anti-tank gun. It had initially been planned to produce the 6pdr in the US under the lend-lease agreement (4,242 guns were eventually delivered for British use) but in May 1941 the US approved the production of the 6pdr as the 57mm M1 Gun. The US M1 guns had a longer barrel than their British counterparts and many smaller differences in manufacture. The US, like Britain, mounted the gun on vehicles such as the M3 half-track – the T48 Gun Motor Carriage. By the end of the war the US has produced over 15,600 M1 anti-tank guns.
Ordnance QF 75mm was developed from the 6pdr, the 75mm guns were manufacture by boring out the 6pdr’s barrel to enable it to fire the US 75mm M46 HE round. The QF 75mm was fitted to a number of British armoured vehicles from 1943 onwards.
RAF De Havilland Mosquito Mark XVIII ‘Tstetse’ with Molins QF 6pdr (IWM)
The 6pdr was a simpler gun to manufacture than its predecessor but despite being effective throughout the war it too was surpassed by a heavier gun, the QF 17pdr AT gun, which was developed in the early 1940s, the 17pdr was accepted for service in May 1942 but the 6pdr remained in service alongside the heavier guns.
After the end of the war the 6pdr continued to see use with a number of countries including Israel during the 1950s, the Irish Army and South Korea during the Korean War. The 6pdr remained in British service until 1951, before being replaced entirely by the 17pdr.
The British Army entered the First World War with very few mortars, and certainly none at the battalion level. As the stalemate of trench warfare set in and the effectiveness of enemy mortars became clear it was decided that trench mortars of various sizes would be needed.
Nicknamed ‘plum pudding’ or ‘toffee apple’ mortars after their projectile’s characteristic shape, the 2 inch Medium Mortar or 2 inch Trench Howitzer, was one of Britain’s first effective light trench mortars to be introduced.
Right-side view of the 2in Trench Mortar (Matthew Moss)
Trench mortars were the army’s most forward artillery, right up on the front line. These short range weapons were able to throw large, high explosive projectiles, short distances across No Man’s Land at the enemy trench system opposite. The 2 inch mortar was considered accurate out to 350 yards with a maximum effective range out to just under 600 yards.
Introduced in 1915, the 2 inch mortar was originally crewed by men taken from the battalion it was stationed with, along with some specialists from the Royal Artillery. However, with the introduction of the 3 inch Stokes mortar which was operated by the infantry themselves the 2 inch mortars became the sole responsibility of the Royal Field Artillery.
A young gunner loads a 2in spigot mortar bomb into his mortar (Imperial War Museum)
Mortar positions were often in secondary trenches just behind the infantry’s frontline. This was to help protect the infantry from potential counter-battery fire. The trench mortars were often deployed to sectors to provide counter battery fire against German minenwerfers or in the run up to an offensive or local action. A British Army report on artillery use, drawn up in February 1917, noted that “Owing to their liability to be destroyed by hostile artillery fire it may often be advisable to defer opening fire with these mortars till the last day of bombardment.” The mortars were also tasked with keeping gaps made in the wire clear and with supporting any feint attacks made by infantry during gaps in the bombardment running up to a larger offensive.
Llewelyn Wyn Griffith, a captain with the 15th Royal Welch Fusiliers and later a novelist, recalled in his war memoir:
“At night a trench mortar officer set his guns in a derelict trench about twenty yards behind the line and carried up his ammunition, heavy globes of iron with a little cylindrical projection like a broken handle. In the morning I moved the men from the bays between the trench mortars and their target, to lighten the risk of loss from retaliatory fire.”
Sometimes the width of No Man’s Land required saps to be cut extending out from the frontline so the mortar rounds didn’t fall short. The 50 lb lollipop-like projectile had a maximum effective range of 570 yards (depending on the size of cordite charge used), and could create a crater 5 feet deep and 14 feet wide. The ideal mortar position was a 6 feet wide by 9 feet deep sandbagged pit with the weapon’s heavy wooden bed at the bottom and room for the crew to load the mortar.
A British 2in Mortar position in Mesopotamia, note the ignitor’s breech is open (Imperial War Museum)
Crews could manage to fire approximately once every two minutes. Much slower than the lighter 3 inch Stokes Mortar and but faster than the heavy 9.45 inch Heavy Mortar. The mortar comprising of just its tube, bed, stand and ignition system weighed 320 lbs (145kg), not including the accompanying tools and the Temple silencer system which could be fitted (which weighed 47 lbs or 21 kg alone).
Typically manned by a 5 man mortar crew comprising of an NCO, gunners, and ammunition bearers. To operate the 2 inch mortar a cordite charge was first placed down the tube, the projectile’s shaft was then inserted on top of the charge, the projectile’s fuse was set and checked and a new blank cartridge chambered in the ignition system. The crew then got clear of the weapon and pulled the lanyard to fire the mortar. To reload the crew ran a clearing stick down the tube and then repeated the loading process.
The business end, a view down the length of the mortar (Matthew Moss)
Interestingly, the 2 inch Medium Mortar, like the larger 9.45 inch Heavy Mortar used a cut-down rifle, which screwed into the ‘breech’ end of the mortar tube. This particular mortar has an 1894-dated cut down Lee-Enfield MkI as its ignition system, the cutdown rifle has a wooden insert in its magazine well but it still has its rear volley sight attached. This reusable system replaced the T-tube Friction ignitor, which was in high demand by Britain’s bigger guns. The Lee-Enfield-based system enabled the cordite propellant charges to be ignited by a blank .303 round instead. The rifle’s trigger was pulled with a lanyard from nearby cover. These cutdown ignitor rifle are sometimes confused for Obrez-style Lee-Enfields.
A close up look at the 2in Mortar’s SMLE ignitor (Matthew Moss)
The weight of the cordite charge used dictated the range while a variety of different fuses were used with the projectiles, these screwed into the nose of the bomb. The sphere was about 9.3 inches in diameter with a 2 inch thread for the fuse at its head and a cup for the 22 inch long, 2 inch thick solid cast iron stick or spigot at its base. The sphere was filled with high explosive (Amatol or Ammonal). The high explosive bombs were painted white with a green or pink stripe around their middle.
They were often deployed in batteries of four with three Royal Field Artillery medium mortar batteries attached to each division. The mortars were predominantly tasked with cutting enemy barbed wire and destroying enemy trenches and forward positions, such a machine gun nests.
Men of the Royal Army Ordnance Corps playing cards on a dump of trench mortar ammunition during Battle of the Somme (Imperial War Museum)
Captain Griffith described a battery of 2 inch mortars opening fire on enemy lines:
“A pop, and then a black ball went soaring up, spinning round as it went through the air slowly; more pops and more queer birds against the sky. A stutter of terrific detonations seems to shake the air and the ground, sandbags and bits of timber sailed up slowly and then fell in a calm deliberate way. In the silence that followed the explosions, an angry voice called out in English across No Man’s Land, ‘YOU BLOODY WELSH MURDERERS.’
The 2 inch medium mortar entered service in spring 1915 and remained in use into 1917 with British and Empire troops. It was used on the Western Front and in Mesopotamia. Over 800 were ordered initially with 675,000 bombs, many of the mortars were made in railway and agricultural machinery workshops, allowing larger factories to focus on more complex weapons. The 2 inch mortar was superseded by the larger bore Newton 6 inch mortar later in the war. Some of the remaining 2 inch projectiles were re-purposed as makeshift anti-tank mines, buried in no man’s land in anticipation of possible German tank attacks.
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The interwar period saw many countries under invest in their militaries, Britain was no exception. One area of equipment that went lacking for many years was adequate anti-tank weaponry. This was finally addressed in the mid-1930s with the Superintendent of Design at Woolwich arsenal developing the 2pdr anti-tank gun, which adopted in 1936.
Prime Minister Winston Churchill watches a demonstration of a 2pdr AT gun (Imperial War Museum)
Officially designated the ‘Ordnance QF 2-pounder Mark IX’, the 2pdr was an attempt to provide a light and mobile high velocity anti-tank gun which was relatively cheap to produce and effective against contemporary tank armour. It was also intended that the gun would itself be mounted in armoured vehicles and tanks.
In 1934 development contracts were awarded to Woolwich and the Vickers-Armstrong company for the design of carriages for the new gun, the Vickers Mark I and the Mark II from Woolwich. The Mark I had a slightly different armour shield and leg design.
These two carriages were tested against one another with trials taking place from November 1935 through to the summer of 1936. The Vickers design initially won out and the first order for 44 guns was placed in 1936. A subsequent re-evaluation of an improved version of the Woolwich carriage found it superior and the Mark II carriage was adopted.
The business end, note the 2pdr’s tall armour shield to protect the crew (Matthew Moss)
The 2pdr fired a 40×304mmR armour piercing round which weighed 2lbs 6oz or 900g and was effective out to 1,000 yards against up to 1.5 inches of armour. It had a four man crew and was capable of firing up to 20 rounds per minute. It had an all steel barrel with a removeable breech ring and a vertically sliding breech block. The gun had an innovative and very stable three-legged collapsible platform, rather than a split-trail carriage, that also allowed the gun to be rotate through 360 degrees when its road wheels were removed. The 2pdr had a semi-automatic action with a hydraulic/hydrospring recoil system which used hydraulic fluid to absorb the gun’s recoil. This allowed the gun to be rapidly aimed and fired despite recoiling approximately 20 inches (or ~50cm).
A number of variants of the gun were developed during the war, with the original Mark IX, a simplified production model the Mark IXA, the Mark X which had a barrel made of higher-yield steel which was not autofrettaged – making it easier to manufacture and the Mark XA which was produced to lower tolerances and able to use the Littlejohn adapter.
Here’s a Royal Army Ordnance Corps training film on the 2pdr (courtesy of the AWM) in full:
Weighing around 1,800lbs or 816kg (or 4/5 of an Imperial Ton) the 2pdr was deemed to be too heavy for the infantry it had been designed for and in 1938 it was transferred to the Royal Artillery. Typically the guns were grouped together in anti-tank battalions each with three batteries made up of four troops which operated four guns each. That’s 16 guns per battery and 48 guns per battalion. Typically a battalion would be assigned to support a division. They were designed to be towed by a variety of vehicles with trucks, jeeps and Universal Carriers often being used.
The 2pdr was typically equipped with a No.24B 2x sighting telescope, located on the left side of the gun. It also had an iron sight but the armoured shield had to be lowered to use it. On the right side of the breech an ammunition box, holding 16 rounds was be stored for easy access, another two boxes holding 8 rounds each could be strapped to the carriage behind the ammunition box (described as the emergency ammunition box). The rest of the ammunition in twelve more 8-round containers, giving a total of 96 rounds assigned to each gun, was carried on the truck which towed the gun.
A view of the gun from behind its shield, on the left the gunners sear, the aiming scope, traverse and elevation controls and on the right the space for the ammunition boxes (Matthew Moss)
The gunlayer sat in a small seat mounted to the carriage and the loader knelt to the right of the breech. The gun was turned by a small traversing wheel operated by the gunlayer. In low gear one rotation of the wheel would turn the gun 3 degrees, in the higher gear (activated by the right foot pedal) one rotation traversed the gun 20 degrees. This meant the gun could be traversed the full 360 degrees with 18 rotations of the wheel. The right hand wheel controlled elevation of the barrel. The gun was fired by the gunlayer using the left foot pedal or two emergency firing levers if the pedal became inoperable. While the breech would typically open automatically ejecting the spent shell casing after firing a breech handle was also located on the right side of the breech.
The 2pdr’s foot pedals: traverse gear on the right, fire pedal on the left (Matthew Moss)
The gun could be brought in and out of action in under a minute, including removing or replacing the road wheels. The 2pdr could, however, be fired from its road wheels, this was described as ‘emergency action’. The wheels limited the traversing arc of the gun and turns greater than 14 degrees right or 10 degrees left had to be done by lifting the gun’s trail and turning it manually. While less stable and accurate the gun could be brought into action from being towed in less than 20 seconds.
In 1939, the British Expeditionary Force to France embarked with 509 2pdrs. During the 1940 Battle for France the 2pdr was found to be an adequate anti-tank gun. One problem identified with the 2pdr was that its armour shield, designed to protect the crew, gave it a quite high profile making it easier to spot and more difficult to conceal.
A view of the breech and down the barrel of a 2pdr (Matthew Moss)
During the retreat to Dunkirk and subsequent evacuation all of the guns brought to France were lost. 60% of Britain’s 2pdr Anti-Tank guns were left behind in France, just 333 guns which hadn’t accompanied the BEF remained. Many of the guns captured after the Dunkirk evacuations entered German service under the designation 4.0cm Pak 192(e).
As the thickness of enemy armour increased the 2pdr began to struggle. The German Panzer II had 1.2 inch thick frontal armour while the Panzer III more than doubled this to 2.8 inches. On paper at least the 2pdr, firing a APHV round, could penetrate up to 2.2 inches of armour at 500 yards (460m). But in reality the Panzer III was the last German tank the 2pdr could expect to engage with a decent chance of success. With the emergence of the later mark Panzer IV, with their 50mm or 2 inch thick frontal armour, they became much less effective. If not adequately concealed gun crews could expect to be engaged by AP and high explosive rounds from the Panzers at ranges outside their effective engagement range.
Despite this, however, the 2pdr proved to be a more than a match for Japanese tanks such as the Type 95 Ha-Go light tanks, which had armour less than an inch thick. At the Battle of Muar in Malaya, in January 1942, Australian 2pdrs, of the 13th Battery, 4th Anti-Tank Regiment, knocked out six, of possibly eight or nine, Japanese tanks as they attacked up a road near Bakri. Sgt. Charles Parsons, commander of one of the guns was awarded the Distinguished Conduct Medal (DCM). Interestingly. the Australians referred to the QF 2pdr AT Gun as the “Tank Attack 2pdr” apparently a designation common to Australian anti-tank weapons as they also called the PIAT the Projector, Infantry, Tank Attack.
The 2pdr remained capable of destroying heavier Japanese tanks too, the Type 97 Chi-Ha medium tank had at 1 inch thick front armour which the 2pdr could easily penetrate at ranges of over 1,500 yards.
Photograph of knocked out Japanese Type 95 tanks during the Battle of Muar (Imperial War Museum)
Lieutenant Ben Hackney of the Australian 2/29th Battalion described the engagement during the Battle of Muar:
“A couple [of tanks] attempted to turn and make a get-away but still those boys with the anti-tank guns were sending a stream of shells into them. At last they could not move forward any further and became as pill-boxes surrounded, sending fire in all directions; until one by one they were smashed, set on fire, and rendered useless and uninhabitable. There came then from the tanks sounds which resembled an Empire Day celebration as the ammunition within them burnt, and cracked with sharp bursts, and hissed, with every now and again a louder explosion as larger ammunition ignited.”
In addition to being used as a towed anti-tank gun the QF 2pdr was used in a wide range of light and cruiser tanks, it provided the main armament for the Matilda II, the MKVII Tetrach light tank, the first six Marks of the Valentine infantry tank, the MKI & MKII Crusaders, the Cruiser Marks I to IV, the Covenanter tanks and it was also used in the Australian cruiser tank, the AC1 Sentinel.
MKI AEC Armoured Car equipped with a 2pdr (Imperial War Museum)
It was also widely used to arm armoured cars including the Daimler, the MKI AEC, the MKI Coventry and the Marmon-Herrington Armoured Car. In the desert it was also mounted and operated simply on the back of adapted trucks – known as Portees. Trucks built by Chevrolet, Ford or Morris were all pressed into service to create Portees. The 2pdr was deployed on its tripod on the truck bed with its wheels removed. In this setup the guns became highly mobile with the crew able to operate the gun from the truck moving in and out of action rapidly. They were widely used in North Africa with a number of medals including a Victoria Cross being awarded to men who manned them.
Second Lieutenant George Ward Gunn, J Battery, Royal Horse Artillery, was awarded a posthumous Victoria Cross for his actions in November 1941 during Operation Crusader. Gunn commanded a troop of four Portee 2pdrs which engaged a German counter attach, with all but one of his guns knocked out and the remaining gun’s crew killed and the truck on fire, Lieutenant Gunn manned the gun himself, engaging the enemy at 800 yards, he managed to destroy two Panzers before he was killed.
The example we are examining began its life as a Mark IX but was subsequently upgraded into a Mk XA, capable of using a Littlejohn adaptor. The Littlejohn adapter used the squeezebore principle, the device was about a footlong with a smooth tapered bore. With the adaptor fitted to the muzzle of the 2pdr the round would be compressed by the taper going from 40mm to 30mm in diameter. This had the effect of increasing muzzle velocity giving the round a flatter trajectory and more energy. An armour-piercing, composite non-rigid round with a tungsten core was used, designated the APSV (from ‘armour-piercing super velocity’). It had the effect of almost doubling the muzzle velocity of the APSV round when compared to the original 2pdr AP shell. The adaptor was invented by Czech designer, František Janeček, the founder of the JAWA motorcycle company. The Mk I Littlejohn device entered production in January 1943 and the Mk II was approved in May 1944.
While design of the 6pdr anti-tank gun, the 2pdr’s replacement, had been completed by 1938, production of the gun did not begin until 1942. Following the huge losses at Dunkirk and with invasion believed to be imminent the decision was taken to focus on the 2pdr gun as its production line was already established. They remained in service throughout the war equipping anti-tank batteries and armoured vehicles. Over 34,000 2pdr anti-tank guns were produced between 1936 and 1944, over 11,000 of these were deployed as anti-tank guns on carriages while the rest were used in various vehicles.
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Specifications:
Overall Length: 135.5in or 343cm
Weight: 1,800lbs or 816kg
Action: Semi-automatic, hydrospring recoil buffer
Calibre: 2pdr or 40×304mmR
Elevation: -13 / +15 degrees
Traverse: 360 degrees
Rate of fire: 20 rounds per minute
Bibliography:
Anti-Tank Weapons, T. Gander, (2000)
British Anti-Tank Artillery 1939-45, C. Henry (2004)
‘British equipment Losses at Dunkirk and the Post-Dunkirk Situation’, WWII Equipment.com, D. Boyd, (source)
2 Pounder Anti-Tank, Royal Army Ordnance Corps (RAOC) training film, via AWM, (source)
The Armourers Bench 