We’re lucky enough to have some unique colour footage showing the of testing of some of these explosive devices and in this article we will examine an incendiary-filed case.
In this piece of 16mm colour footage, filmed in 1940 by Captain Cecil V. Clarke, we see what appears to be an attaché case containing three medium-sized bottles, which likely contains a mix of petrol and paraffin or some white phosphorus, prepared for testing at the bomb range at Brickendonbury in Hertfordshire, a Special Operations Executive training and research centre codenamed Station XVII. It’s believed that these films may have been produced as teaching aids for the agents trained at Station XVII and this film may have been shown during a lecture.
While incendiary briefcases, attaché cases and even suitcases are listed in the 1944 SOE Descriptive Catalogue of Special Devices and Supplies they were quite different from this case. They were primarily designed for the quick destruction of documents and items carried inside them. They used sheets of potassium nitrate to burn the case’s contents.
The incendiary case seen in this footage on the other hand appears to be designed to be clandestinely placed and detonated with a delay fuse, to set nearby flammable objects on fire. What was described as a ‘Delayed Action Incendiary’.
In this footage of another separate test we get an idea of the destructive capability of just one of the bottles.
It’s possible that this incendiary case was a proof of concept test for the later cases or perhaps a demonstration of a concealed incendiary device Station XVII were working on. SOE developed a large number of bespoke explosive devices for various missions, so while this device may not have become ‘standard issue’, it may have been developed for a specific purpose.
During the Second World War Britain’s Special Operations Executive (SOE) developed a whole series of sabotage devices for use behind enemy lines. Using unique archival footage this series of short videos examines some of the weapons developed for use by SOE agents in occupied Europe. We begin the series with a look at the history and development of Explosive Coal. Explosive coal was designed to explode inside fireboxes, furnaces and coal stores hampering enemy infrastructure.
I came across this footage while doing some research in the Imperial War Museum’s online catalogue. This piece of 16mm film was filmed by Cecil Vandepeer Clarke, a British engineer and sabotage expert who was a member of the Special Operations Executive and worked at a number of weapon research and development centres including MD1 at Whitchurch and SOE Station XII at Aston.
SOE or Special Operations Executive were a clandestine force tasked with conducting irregular warfare behind enemy lines including sabotage, assassination, intelligence gathering an small scale raiding. One of the sabotage methods developed was introducing an explosive charge into the boiler firebox of a ship or a locomotive or a power station or factory’s furnace. This achieved by disguising the explosive as either a piece of fuel like coal or wood or even as a dead rat – which might be tossed into a firebox or furnace to be disposed of.
The idea of ‘Explosive Coal’ wasn’t new. The idea originated from the US Civil War, when Confederate Captain Thomas Edgeworth Courtenay designed a piece of cast iron, with a cavity which could be packed with gun powder, that looked like a lump of coal. The Courtenay described them as ‘Coal Torpedoes’, their aim was to damage a steam ship’s boiler enough to cause a catastrophic secondary explosion. While several vessels may have been damaged or sunk by these Coal Torpedoes, the claims are difficult to confirm.
It seems the idea of a coal bomb was resurrected in 1940 and initially a ‘Coal Borer’ was developed and available for use in theatre by mid-1940. The borer could be used by agents to make holes in lumps of coal which could be filled by plastic explosive and a detonator. This was soon superseded by an Explosive Coal Kit which included moulded fake coal and paints to allow agents to match the colour of local coal. The kit included instructions on how to prepare and use the coal bomb.
Arthur Christie, a lab assistant at Station XII, is quoted at length in Des Turner’s book on Station XII. Christie remembered being asked to drill large holes in some coal:
“Another task was collecting the biggest lumps of coal that I could find in the storeroom and taking them to the lab. I had no idea what they wanted them for; it was seldom explained to me and, when it was, it was often as clear as mud. My instructions were to try to drill a large hole in each piece of coal without shattering it. I tried with a brace and a six-inch long tube that had a serrated end. I found that, if too much pressure was applied, the coal would disintegrate. I thought, I wonder what the hell they want this for? Don’t ask, just do it, and I did manage to drill three lumps of coal. I placed the drilled coal on the table of the MI room and set off for the officers’ dining room to inform the CO that I had been successful. I was told to insert about a quarter of a pound of PE and a detonator into the hole and glue the coal dust back over it. The mud in my brain now began to clear. The lump of coal could be placed in the coal tender of a locomotive and find its way into the firebox, or perhaps into the furnace of a factory. Later the PE was dyed black, which was better than using coal dust and glue. This idea led to plastic explosive being moulded into a multitude of objects and colours to fool the enemy.”
Frederic Boyce & David Everett, in their book SOE: The Scientific Secrets, credit Station XV with the development of a moulded clam-shell design using dyed Herculite plaster and coated with real coal dust. A photograph of this can be seen in the SOE’s Descriptive Catalogue of Special Devices and Supplies, along with ‘Explosive Wood’, or as it was officially known ‘Wooden Logs, Explosive’.
Eventually this was replaced by a bomb based around a charge in a metal casing that allowed liquid plaster to be poured around it, simplifying production and removing any sign of a seam. The coal bombs were detonated by a No.27 Detonator to which either a match headed safety fuse or a time delay fuse was attached.
Once the danger of coal bombs was discovered by the enemy it was also believed that they would have considerable a psychological impact and also cause the enemy to expend considerable resources on protecting and checking coal supplies.
The ‘Explosive Coal’ we see in the footage appears to actually be an incendiary bomb, producing a large amount of flame and heat. This would have been ineffective in a boiler but with a time delay or other sort of fuse it may have been very effective in causing a coal bunker fire aboard a ship, in a factory store, at a coal depot or in a locomotive’s coal tender. Coal fires are extremely difficult to contain and put out.
How effective Explosive Coal was is unclear but it is believed that coal bombs were used by both the SOE and their American counterparts the OSS. Boyce & Everett estimate that about 3.5 tons of explosive coal was made between 1941 and 1945. I’m unsure how many of these were explosive and how many were incendiary, like that seen in the footage here, but it’s a fascinating asymmetric method of targeting enemy infrastructure at the most basic level.
The Diemaco M203A1 is a development of the M203 40x46mm low velocity grenade launcher. The M203 was initially developed by AAI to replace the Colt XM148 which proved overly complex when tested in Vietnam.
The Diemaco M203A1 improves on the earlier launcher by incorporating its sight into the mount rather than being atached to the top of the barrel. The Diemaco M203A1 should not be confused with the Colt-manufactured M203A1 in US service. The Diemaco launcher is offered alongside the C7 and C8 rifles made by Diemaco (now Colt Canada).
Diemaco developed the M203A1 so it has a longer action, with the breech opening further to allow the firing of all 40×46 mm LV grenades including less than lethal baton rounds. It can also be mounted on all AR-patterned rifles as well as the Steyr AUG.
Like the original M203 the launcher can be operated by either a left or right handed users. The original model had an iron sight assembly has dual azimuth adjustment knobs and an elevation dial, this model, however, has a simplified tangent sight. Diemaco stated that the M203A1 has a maximum effective range of 400m (440 yd) with a muzzle velocity of 78 m/s (260 ft/s).
The M203A1 was tested by the UK’s special forces in the late 1990s, when they evaluated the Diemaco SFW carbine, which was subsequently adopted as the L119A1. The Heckler & Koch M320 GLM (HK AG36) has since been adopted by the British Army.
Calibre: 40 mm
Loaded Weight: 2.15 kg (4.74 lb)
Empty Weight: 1.85 kg (4.08 lb)
Overall Length: 318 mm (12.52 in.)
Barrel Length: 228.6 mm (9 in.)
Overall Height: 140 mm (5.51 in.)
Rifling: Right Hand Twist – 6 Lands
Rate of Twist: 1 turn in 48 in. (121.9 cm)
The US entered the Great War with no tanks of their own – by the end of the war they had designed and built their first tank, collaborated on a leviathan heavy tank with Britain and built their own copy of the French FT. In this video we look at how the US Army hit the ground running and formed two tank corps and built their first tanks.
In recent videos we’ve looked at all of the US Army’s early tanks, here’s a round up:
The tinny 3-ton Ford was the first American designed and built tank. Aiming to use readily available parts and materials it took inspiration from the French Renault FT but was smaller and lacked the FT’s revolutionary turret. The Ford was only lightly armoured and did have the best cross country handling. Check out our full article on the Ford here.
The MkVIII was a truly ‘international’ effort with the US, UK and France all working on the project. The US and UK provided the mechanical components while France provided a factory to assemble the formidable vehicles. The MkVIII wasn’t ready in time to see action during the war but remained in US service into the 1930s. Check out our full article on the MkVIII here.
The US also sought to produce their own licensed version of the French Renault FT, making some slight changes the tank was adopted as the M1917 but despite production being well underway by late 1918, none of the M1917s reached the front. Instead they became the backbone of the US Army’s interwar tank force. One even climbed a mountain!Check out our full article on the M1917 here.
In 1940, following the evacuation from Dunkirk the British Army was in desperate need of small arms, with over 100,000 rifles left behind in France. In dire need of rifles Britain turned to the US and its huge industrial base and approached a number of companies about tooling up to produce Lee-Enfield Rifle No.4s. Savage Arms took on one contract and projected production of 1,000 per day but establishing production of a rifle US companies didn’t have the tooling and gauges for would take time.
Remington was also approached by the British Purchasing Commission and asked if they could manufacture up to 400,000 rifles. Remington estimated it would take up to 30 months to tool up for No.4 production. However, Remington believed that if they could lease the old tooling previously used at the Rock Island Arsenal to produce M1903s, from the US Government, they could tool up to produce the M1903 in just 12 months. It was suggested that the tooling be adapted to produce rifles chambered in the British .303 cartridge. Some ergonomic changes could also be made so the rifles mimicked the British No.4.
On 12th December 1940, the British government issued a Letter of Intent to Remington for the manufacture of 500,000 rifles in .303 British. Some sources suggest the British agreed to an advanced payment of $4,000,000. Much of this covered the lease, transport and refurbishment of the M1903 tooling. The rest went on the purchase of raw materials and the necessary accessories for half a million rifles.
The tooling lease was agreed in March 1941, and the US Government also supplied 600,000 stock blanks which had been in storage in exchange for ammunition produced by Remington. With the passage of the Lend-Lease act, on 11th March, the Remington contract came under the control of the US Government, rather than a private order. Remington received the last tooling shipments from Rock Island Arsenal on 22nd April, and by the end of May had the production line up and running.
A contract to produce the hybrid rifles at a cost of $5 per rifle was agreed in late June. Remington’s engineers began setting up the equipment and working out an ad hoc production layout that would allow 1,000+ rifles per day to be built. At least four pilot models were built, with some of these guns being sent to Britain. The rifles were reportedly received in September 1941, and following preliminary examination were described as “very successful”. Four of the rifles were distributed for further testing but by the end of 1941 the project had been abandoned.
Remington made a number of external and internal changes to approximate the British No.4. They fitted a front sight post with sight protectors which was moved further back from the muzzle to enable the rifle to mount a Rifle No.4 spike bayonet. As such the upper barrel band does not have a bayonet lug.
Many of these parts are still in-the-white, unfinished, including the barrel, barrel bands, floor plate, front sight assembly, rear sight assembly and the bolt itself. The bolt does, however, have a parkerized cocking piece.
The hybrid also moves the rear sight back onto the receiver, which necessitates a longer piece of wooden furniture covering where the M1903’s ladder sight would normally be. The style of rear sight was also changed to a two-position flip sight with apertures for 300 and 600 yards mimicking those seen on the No.4 Mk2.
They also redesigned the charger guide to support the Lee-Enfield-type chargers rather than the M1903 stripper clips. The bolt was adapted to work with Britain’s rimmed .303 round, with the extractor modified for the British cartridges wider, thicker rim.
The rifle did not have the Lee-Enfield’s detatchable box-magazine, instead retaining the M1903’s 5-round internal magazine. The magazine follower does not appear to have been altered either. Markings on the rifle are minimal and include a ‘7’ on the front sight post, a ‘B2’ on the bolt handle and a ‘2’ stamped on the magazine follower. No roll marks or serial numbers appear to be present.
The rifle’s stock has also been adapted, so instead of a straight wristed-stock a piece of wood has been spliced in to create a Lee-Enfield style contour, forming a semi-pistol grip. The stock is marked with the inspector marks ‘WJS’, which indicate the stock was originally inspected by W.J. Strong and accepted between 1918 and 1921, as well as a pair of later Springfield Armory inspection cartouches: ‘SPG’ – the initials of Stanley P. Gibbs, who was an inspector at Springfield Armory between 1936-1942 and ‘GHS’ – the initials of Brigadier General Gilbert H. Stewart (GHS), Springfield’s commander in the late 1930s- early 1940s. This would suggest that the stock was refurbished at Springfield Armory before being transferred to Remington where it was subsequently adapted.
In August 1941, the US began its re-armament programme and in September the British contract with Remington was cancelled. At the same time production in Canada and at Savage’s J. Stevens Arms division in the US had gotten underway and it was decided that the adapted hybrid .303 M1903s developed at Remington was no longer needed. The hybrid contract was formally cancelled in December 1941, and additional .30-06 M1903s and M1917s were taken under the Lend-Lease Agreement to fulfil the needs of the Home Guard. Savage believed that they could significantly increase the number of rifles they could build per day, they managed to enter full production by the end of 1941 and by 1944 had produced well over 1 million No.4s.
Remington went on to produce M1903s for the US military, overcoming issues with the original engineering drawings and the tooling dimensions to eventual produce 365,000 M1903s by mid-1943, before switching to production of the M1903A3 pattern and producing 707,629 rifles. In total Remington produced 1,084,079 M1903-pattern rifles during World War Two.
The Remington .303 M1903 hybrids are perhaps the rarest M1903 variant, with only a handful built. They would likely have been perfectly serviceable rifles and helped plug the desperate gap in Britain’s arsenal. Rapidly moving events ensured that these rifles became a footnote in both the Lee-Enfield and Springfield 1903’s histories.
Special thanks to both Remington and the Cody Firearms Museum for allowing us to take a look at this extremely rare rifle.
The Sten is one of Britain’s iconic Second World War Small arms. Two men are principally responsible for its development Colonel Reginal Vernon Shepherd and Mr. Harold John Turpin a pair of small arms and engineering experts with considerable experience.
Turpin was born in Kent in 1893, served his apprenticeship as a draughtsman in Erith and in 1922, he joined the drawing office at the Royal Small Arms Factory Enfield – Britain’s principal state small arms centre.
Reginald Shepherd was born in 1892, received an Bachelor of Science Degree from Leeds University in 1912. In October 1914, he joined the West Yorkshire Regiment as a second lieutenant, serving in Gallipoli and Egypt. After the war, with his engineering background, he assigned as 2nd Assistant Superintendent at the Design Department at RSAF Enfield in December 1922, and promoted to captain.
The two men found themselves joining Enfield at around the same time. In November 1933, Shepherd, now a major, was appointed Inspector of Small-Arms (Class 2) at Enfield and assisted in getting the Bren light machine gun into service. He remained at Enfield until 1936, when he retired from the army and spent a short spell at BSA before being recalled. In late 1939, Major Shepherd returned to active service and once again took up the position of Inspector of Armaments, this time at the Ministry of Supply Design Department at Woolwich Arsenal.
By the outbreak of the Second World War Turpin had become the senior draughtsman at Enfield and when the development of the Lanchester Machine Carbine began he was paired with Major Shepherd to draw up technical drawings for the gun’s production.
The two men decided that a simpler, cheaper submachine gun could be produced and in December 1940 set about designing it, with Turpin in the lead. During the Winter of 1940-41 the first prototypes were built. Development of the first Sten – the T40, was completed on 8th January 1941, taking just 36 days.
14 pilot models were ordered but only two were completed by engineers at the Philco Radio Works in Middlesex: T-40/1 and T-40/2. The gun was initially designated the ‘T-40’ or Turpin, 1940. By the end of January 1941, it had become known as the ‘ST Machine Carbine’. The ‘Carbine, Machine, STEN, MkI’ was approved for issue on 7th March, 1941, with 100,000 guns ordered.
How did the gun become known as the ‘STEN’ and what did Sten stand for?
We know that the ‘S’ stands for Shepherd and the ‘T’ for Turpin, but what about the ‘EN’ – it is generally accepted to represent ‘Enfield’. Why? Because RSAF Enfield is synonymous with British military firearms. Additionally the Bren light machine gun’s name is a portmanteau of ‘BR’ from Brno, the location of the Czech factory the zb.26/30 originated from, and ‘EN’ for Enfield, the British factory that anglicised the design for British manufacture and service.
Enfield, however, wasn’t where the Sten was designed. Turpin and Shepherd claimed that most of the work on the design had been done out of hours. Additionally, during the winter of 1940, the Armament Design Department was relocated, from Enfield to a former Drill Hall in Cheshunt, Hertfordshire to escape the bombing of London.
While the Sten may not have been designed at Enfield, the first prototype was partially assembled there with work also done at Turpin’s own home workshop. A further 46 pre-production pilot models were later ordered from RSAF Enfield, in February 1941.
Intriguingly, early accounts suggest that ‘EN’ may have stood for ‘England’ – not ‘Enfield’. In October 1942, the fifth instalment of ‘Know Your Weapons’, a semi-official series of weapons manuals printed by the publisher Nicholson & Watson, explains that ‘EN’ did in fact stand for ‘England’.
In June 1943, Turpin penned a semi-anonymous article for ‘The Model Engineer’, about the design and development of the gun, which repeated this claim. An October 1943, article in the US Popular Mechanics magazine, entitled ‘Machine Guns from Backyard’, includes a supposed quote from the inventors explaining that the “E and N stood for England.”
A more official account came in June 1949, at a hearing of the Board of the Royal Commission Awards to Inventors (a board set up to reward inventors who had done important war work). One of the board members Lord Justice Sir Lionel Cohen asked Shepherd: “Why was it called the Sten?” The colonel replied: “It was called the Sten by the then Director General of Artillery. The ‘S’ was from my name, the ‘T’ from Mr. Turpin, who was my draughtsman and who did a very large amount of the design, and the ‘EN’ was for England. That is the origin of the name, for which I accept no responsibility.” This suggests that the ‘EN’ standing for ‘England’ may have originated from the upper echelons.
Sadly, there was no officially published explanation of the name as official manuals rarely go into superfluous detail. In 1948, however, Ian Hay published R.O.F. The story of the Royal Ordnance Factories, 1939-1948 in which he stated the ‘EN’ was a reference to the Enfield factory. Similarly, another early published account, D.M. Ward’s 1946 The Other Battle, a history of BSA, also suggested it represented the factory name.
In truth it is difficult to know exactly what the ‘EN’ stood for. It may be that both Enfield and England were discussed and used by various individuals and offices. There may have been an element of propaganda to including ‘England’ in a weapon’s name which led senior officers to push this in the press and direct the gun’s inventors to suggest this was the case too. Of course the authors of those earlier books may have mistakenly believed ‘EN’ stood for Enfield, as it does in Bren. Personally, I’m inclined to follow the primary sources attributed to the two men responsible for the design, and believe it initially stood for England.
Shepherd was awarded an OBE in January 1942, and became the Assistant Chief Engineer Armament Design (A/CEAD), he was promoted to Lt. Colonel in August 1943. He retired from active duty at the age of 55, in January 1947, and was removed from the reserve list. He was granted the honourary rank of colonel. He died in April 1950, aged 58. Turpin retired from RSAF Enfield in 1953, and died in April 1967, aged 74.
Beyond a pair of discretionary payments, £1,500 to Shepherd and a small payment of £200 to Turpin, neither man was officially rewarded as they were deemed to have essentially done what they were paid for, designing small arms. Scant reward and recognition for a weapon which became one of the key wartime small arms of the British and Commonwealth forces.
Our thanks also to Jonathan Ferguson, of the Royal Armouries, for sharing his thoughts on the ‘Enfield’ vs ‘England’ debate.
The Sten Machine Carbine, P. Laidler, (2000) R.O.F. – The Story of the Royal Ordnance Factories, 1939-1948, I. Hay, (1949) The Other Battle, D.M. Ward, (1946) The Sterling Submachine Gun, M.J. Moss, (2018) The Sten Gun, L. Thompson, (2012)
‘Sten & Bren Guns’, Know Your Weapon #5, (Oct. 1942)
‘The Sten Carbine’, Model Engineer, 3 Jun. 1943, H.J. Turpin Board of the Royal Commission Awards to Inventors – 1946-49
‘Machine Guns From Backyard’, Popular Mechanics, Oct. 1943
Last summer I had the chance to visit the newly renovated Cody Firearms Museum. With the ongoing Coronavirus Pandemic I thought now was a good time to finish my walk-around video taking a look at the new museum.
The $12 million renovation has also allowed the museum to become much more interactive too with working models, touch screens and shooting simulators.
A new intuitive layout lets you explore firearm history either by chronology or by theme. In the photo above we can see some of the displays in the chronological gallery that shows the evolution of civilian and military firearms from their invention to the present.
One of the features I really liked was that many of the cases can be viewed on both sides allowing you to see all around the firearms.
Around the exhibits are touch screens where you can call up more information, first hand war stories and even animations of how various firearms work.
There is also a gallery of ornately decorated firearms which includes some incredible pieces.
Unsurprisingly, the military gallery was one of my favourite parts of the museum with dozens of guns organised by conflict and period.
One of the best features of the original museum has also been retained, a recreation of a gun factory’s drafting room and machine shop.
One of the most interesting little sections is a recreation of a general store showing off some of the items that companies like Winchester made alongside their well known firearms.
Downstairs is a space dedicated to experimental prototypes and a rolling wall of cases that include examples of hundreds of types of firearms and ammunition.
The newly refurbished museum puts the collection front and centre in a way that will enthral the average museum-goer and satisfy any avid gun enthusiast.
Developed in the late 1960s and introduced in 1969/70 the MPi 69 was Steyr’s entry into an already crowded European submachine gun market. Heavily influenced by the Israeli Uzi it had a bolt which telescoped over the barrel and fed from a box magazine that was inserted through a magazine well-come-pistol grip.
The MPi 69 weighed 6.5lbs (2.93kg) unloaded and had a polymer lower receiver into which a stamped metal upper inserted. Unlike the Uzi it had a collapsing, rather than folding stock, similar to the M3 submachine gun’s, and was cocked not by a handle but by pulling the sling (which was acted on the bolt) to the rear.
The MPi 69 remained in production into the early 1980s when it was replaced by the improved MPi 81. Moving away from the slick-cocking ‘gimmick’ the MPi 81 had a conventional, non-reciprocating, charging handle on the left side of the receiver. The MPi’s polymer lower allows it to be a pound lighter despite being slightly longer as a result it also balances better than the standard Uzi carbine.
The MPi submachine guns fire from an open bolt and had a 10in barrel and has a push through safety with settings for safe, semi and full auto and unlike the Uzi it does not have a grip safety – simplifying manufacture.
The MPi also has a progressive trigger which when set to full-auto will allow the user to fire semi when pulled to the first stage and full when pulled fully to the rear. While the MPi 69 had a cyclic rate of around 500 per minute, the MPi 81 increased this rate to ~750rpm.
The MPi can be field stripped by simply rotating the receiver end cap up 90-degrees and pulling the bolt out the rear. The gun can be further stripped but the moulded polymer lower receiver can be difficult to remove from the upper. Like the Uzi the barrel nut is unscrewed to remove the barrel.
It is unclear just how many MPi submachine guns were produced but they didn’t see any significant contracts beyond a few small sales to police forces and militaries.
The MPi 81 remained in production into the early 1990s when it was replaced by the smaller and more compact Steyr TMP in 1992. In turn the TMP design was sold to B&T a decade later.
Our thanks to the collection that let us take a look at this MPi 81 and to our friend Miles Vining for sharing some of his shooting footage of the MPi 81 with us, check out his video here and more of his work at www.silahreport.com.
Here’s a short video looking at how the unusual Hotchkiss Universel deploys from its compact, folded position. The whole process takes just seconds. Impressive engineering but within a couple of years the Universel would be surpassed by far more compact, ergonomic and serviceable designs like the Uzi and PM-63.