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WW2 Japanese AT Weapons

Kaenbin

Nation Flag IconJapan, 1939, Atk weapon – 1,200

There is a saying, Proper Preparation and Planning Prevents Piss Poor Performance (also known as the 7 P’s). In 1939, the Imperial Japanese Army proved this to be true by winning a battle against an overwhelming enemy armored force, without a single tank of their own. At the heart of this preparation was a small bottle of soft drink.

Japanese soldiers posing with captured Soviet armor at Nomonhan.

The story starts along the China/Mongolia border, near the town of Nomonhan. In the first part of the 20th century, this wilderness was inaccurately mapped. There was a small patch of land that both the Japanese client of Manchuria and the Soviet client of Mongolia claimed. The competing claims would lead to five months of fighting between the Russians and the Japanese. The Japanese named this war after the town closest to the border, Nomonhan, while the Soviets named it after the river in the area, Khalkhin Gol (the Japanese called the river the Halha).

To recount the entire story of the battle would be a major undertaking, and there are many such works already in existence. However, suffice to say that, from the initial skirmishes starting on the 11th of May 1939, both sides began to escalate, drawing in more men, tanks, guns and aircraft as time wore on.

Development

One of the units swept up in this escalation of forces was the veteran and fully motorized Japanese 26th Regiment, commanded by the competent Colonel Shinichiro Sumi. When his regiment arrived at the logistics base at Hailar on the 22nd of June, Col Sumi dispatched officers to visit the various units that had already been in combat, and find out more details about what facing the Russians would be like. It is almost certain that these officers would have encountered stories of the Soviet’s tanks, the BT-5 and BT-7. At the time, the Japanese infantry would have had what they termed ‘rapid-fire infantry guns’, but today we would recognise them as 37 mm anti-tank guns. These would, of course, wreck the lightly armored BT tanks. However, the 26th Regiment had none of these weapons. Indeed, it was extremely short of heavy weapons, having just six machine guns and an equal number of battalion guns. The other anti-tank weapon the Japanese infantry had was the Type 93 mine, dismissively nicknamed Anpan by the troops, as it resembled the small sweet bread rolls of the same name. This small round mine was fixed to bamboo poles and shoved under the tracks of any attacking tank. The problem was that, on the sandy soil of the area, a tank would push the mine into the ground and not trigger the fuse.

Japanese soldiers of the 72nd Regiment loading into trucks for movement to the front. Type 93 mines can be seen attached to the poles used to shove them under attacking tank’s tracks.
(Source: Unknown Japanese publication, quoted in Coox, 1985)

It is quite possible that, during these investigations, the officers would have interviewed Private, First Class Okano Katsuma from the 23rd Division. During the skirmishes in May he, along with two other men, were assigned as truck drivers to help bring supplies forward. During one such trip, they were chased by a Russian tank. In desperation, PFC Katsuma started to throw cans of petrol off the back of the truck in an attempt to impede the pursuing Soviet tank. Much to the soldier’s surprise, when the tank hit one of these cans, it burst into flame, allowing them to escape.

The idea of petrol as a weapon against tanks and AFVs was not entirely new to the Japanese. Major Nishiura Susumu had been an observer during the Spanish Civil War and had seen the combatants use wine bottles filled with petrol to attack armored vehicles. In July 1937, he had sent a report back to Japan. This was seen with incredulity by the Ordnance Bureau. However, Major Susumu’s insistence convinced them to conduct trials. These failed utterly. In the cold Japanese weather, the stationary tank stubbornly failed to burst into flame. Thus, the Ordnance Bureau concluded there was nothing to this idea.

Back at the supply base supporting the Japanese efforts, Colonel Sumi had no other ideas to help defend his soldiers from tanks, and he had been ordered to move forward to the front. When the Regiment marched out, he left behind 26-year-old 2nd Lieutenant Negami Hiroshi from the regiment’s Quartermaster detachment. He had orders to secure as many bottles as he could from the army supply chain and ship them to the regiment via truck. Lieutenant Hiroshi found the supply dump stocked with thousands of bottles of soft-drink, and he immediately attempted to requisition these. Like in nearly every army ever, the Quartermaster did not want to issue the bottles. ‘Stores are for storing, not for issuing’. Lieutenant Hiroshi’s task was made all the harder, as he could not divulge what he wanted such a large number of drinks bottles for, due to security concerns. It seems odd to consider security in this situation, however, a large portion of the logistics effort was entirely civilian. Indeed, the trucks that the 26th Regiment were mounted in were commandeered from civilian service, and many still were driven by their original owners in their civilian clothes.

Eventually, Lt Hiroshi managed to obtain crates of the soft-drink by being persistent and striking some form of deal with the Quartermasters. He obtained around 1,200 bottles and shipped them to the regiment. The supplies caught up with the soldiers at Chaingchunmiao. There, they were distributed and the men warned not to throw the bottles after they had emptied the contents. Trials were held to determine the best way of creating the weapon. It was determined the best design was to fill the bottle about ⅓ with sand to give it ballast and the ability to be accurately thrown, and the rest topped off with petrol. To complete the weapon, a small wad of cotton, taken from the soldier’s rifle cleaning kit, acted as a bottle stopper and fuse when lit. This weapon was named Kaenbin. There was still one unsolved flaw. The flat open countryside often had a strong wind blowing, which made lighting even something like a cigarette difficult, if not impossible, let alone having to light the wick in battle. With this problem unsolved, each man temporarily filled his bottle with water and tied it to his waist with a string. Lieutenant Hiroshi had acquired enough drink to provide one bottle to every man in the regiment, including Colonel Sumi. There were a few other bottles leftover and these were shared with neighbouring infantry units.

Illustrative picture only: These Japanese bottles were prepared for use as Molotov cocktails during the Sanrizuka Struggle (1966-present) against the Narita International Airport.

To Battle

Starting on the 1st of July, the Japanese launched their counter offensive. They were to cross the river at its narrowest point, forces would hold the bridgehead, and the 26th regiment in its trucks would push round behind the Soviet forces and encircle them, at the same time overrunning the large Russian artillery reserves that had caused so many casualties in the previous two months.

Like so many plans from the Japanese command structure, this plan was powered by no small amount of delusion, passing over some very critical problems that the command structure simply ignored or talked themselves into not believing the issues were important.

The foremost of these was the pontoon bridge to be used to cross the river. It was the only pontoon bridge that the Japanese had in all of China, and it dated from 1900. What is more, there was insufficient construction material. Thus, the bridge was only 2.5 m wide and the pontoons had to be spaced out further than was desirable. The infantry crossing the bridge had to take off their packs. Only one truck was allowed on the bridge at a time, and that had to be unloaded first. Even with these precautions, the bridge still took damage, and so crossing had to be halted every 30 minutes to repair the structure. To make matters worse, the current at the narrowest point of the river was also the strongest, which made the bridge curve.

Japanese soldiers marching across the inadequate bridge over the Halha.

It is no surprise that, by the morning of the 3rd of July, only one of the 26th Regiment’s three battalions was across the river, along with the 71st and 72nd Regiments to hold the bridgehead. The choice was simple, attack with one battalion, or wait for all three to cross. It will come as no surprise that the Japanese chose to attack. Colonel Sumi ordered his men to cross in boats as fast as possible to join the defence, as the lead battalion began its attack.

Faced with a Japanese bridgehead, the Russians reacted immediately. Elements of the 36th Motorized Rifle Division were based at Tamsag. These were the 11th Tank Brigade, 7th Motorized Armored Brigade, and the 24th Motorized Rifle Regiment. In total, they had 186 tanks and 266 armored cars. These were ordered forward to assault the Japanese position. This required a long fast road march in the baking sun and 40 degree Celsius heat. The Soviet armor surrounded the Japanese bridgehead and began probing attacks, while the main column, in no formation, ploughed straight into the lead battalion of the 26th Regiment, and shortly afterwards the remaining two battalions who were trying to advance on foot to catch up.

The terrain of the battlefield was utterly flat and desolate. There were no features, trees or bushes to hide behind, just endless flat soft sandy soil, with very short grass. In such a situation, the tanks should have obliterated the Japanese infantry caught out in the open.

The 71st and 72nd Regiments had access to rapid-fire infantry guns, as well as the 13th field Artillery Regiment, armed with modern Type 90 75 mm guns. Thus, they were able to hold off most of the attacking tanks. Where these guns or Kaenbin were not available, the infantry resorted to Nikuhaku Kogeki (Human Bullet) attacks. In these, the Infantry would hold their ground until the target tank was within about 40 m, then leap up and charge at the tank. The infantry would swarm the tank, attempting to wrench open hatches or cause damage with grenades. This was pure close combat, man against machine in the blistering heat. Soviet tanks would hose their colleagues down with machine gun fire, or, if the crew was quick enough, they could rotate their turret at full speed, throwing Japanese soldiers off. The scalding hot metal plates of the tank’s hull, further heated by running the engine for so long in the direct sun, also proved somewhat of an impediment.

Painting by Tsuguharu Fujita from 1941 showing Japanese Nikuhaku Kogeki teams assaulting Soviet tanks.

At the 26th Regiment, they had no rapid-fire infantry guns. Their only support was from twelve Type 38 75 mm regimental guns. These dated from 1905 and only had HE ammunition. As the tanks bowled towards the 26th Regiment, these guns opened fire at a range of 1,500 m, but were largely ineffective. At 800 m, the handful of Type 90 70 mm battalion guns the regiment owned opened fire, but these could only score a hit with about a third of their shots and were also largely ineffective. At 500 m, the few HMG’s the regiments owned opened fire. As there was no Russian infantry, these machine guns aimed for vision slits, and also had no effect.

A Japanese Type 92 machine gun set up on the plains of Nomonhan. You can clearly see the exposed nature of the terrain and total lack of cover. Two destroyed Soviet armored cars lie in the background.

Then the tanks reached 40 m, and the Nikuhaku Kogeki teams began to attempt to light their Kaenbin. The harsh wind kept preventing ignition. As a tank bore down on him, in desperation, one soldier hurled his unlit bottle. It smashed on the armor of the tank. To everyone’s surprise, the tank burst into flames. Eyewitness accounts describe how a tank struck by Kaenbin burned:

‘…the bottle would shatter, the gasoline contents would splatter quickly, and the sheet of fuel would ignite in the heat of the sun and vehicle. Flames would appear from the bottom of the tank, the way newspaper burns, giving the impression the ground was on fire. When the flames licked the top of the tank, the fire would subside with a puff, for the fuel tank had been entered. Now the inside of the tank would catch fire and burn furiously.’

The suggestion by surviving soldiers was the heat radiating off the armor plate was sufficient to ignite the fuel. However, the accounts miss a few important details. First, from the information we have on ammunition usage, it seems each of the tanks destroyed by Kaenbin were hit by multiple bottles, on average approximately three each, although an accurate figure is hard to determine. This would mean that the tank would be absolutely drenched in petrol, seeping into every opening, especially the engine bay. Here, there are several possible means to ignite the fuel, such as the exhaust, which would be running at several hundred degrees from the long hard drive. Equally, the hours of driving, in the extreme heat, would have meant the transmission in the tank was scaldingly hot.

In the swirling dust, heat haze and smoke-shrouded battlefield, confusion reigned supreme. However, it was a situation the Japanese were ideally suited to. Any officer or NCO would take charge of the men around him, indicate a target and it would be hit by a volley of Kaenbin. Even Colonel Sumi was directing and organizing his soldiers. The Russian tankers were largely ignoring the infantry, trying to concentrate their fire on the support weapons that the Russians assumed to be wreaking so much havoc on their armored force, when it was the infantry who were the main threat. As the battle progressed, some Russian tankers abandoned their vehicles before they were hit, attempting to flee on foot. Those crews that had bailed from burning tanks were also trying to retreat to friendly lines. They had to endure the attention of the Japanese heavy machine guns.

However, the Japanese were not having it all their own way. Casualties were mounting, and on a few occasions, poor coordination between the Battalion Guns and the Infantry meant that Nikuhaku Kogeki teams were killed by friendly fire. By 1500 that afternoon, mere hours after the attack was launched, the Russians withdrew. As they pulled back, they left a field of burning vehicles. These would burn for 3-4 hours after they were hit. Ammunition would suddenly cook-off in the flames, randomly sending turrets flying, or sprays of small arms fire out from their wrecks.

That evening, Colonel Sumi tallied events. The regiment had claimed 83 tanks knocked out, although Col Sumi reckoned this involved some overclaiming. He calculated that the total was around 70. The force, as a whole, had knocked out some 280-230 AFVs from the attacking Russians.

However, the Japanese force was spent. It had taken about 10% casualties and was all but out of ammunition. For example, the 26th Regiment could find just thirty-six Kaenbin. The lead battalion had no ammo left for its Battalion Guns, the other two battalions only had one serviceable gun each, with just one box of ammunition left.

With no hope of resisting the following day, and with Russian Artillery coming more into play, the Japanese began to withdraw. However, through a miscommunication, the lead battalion of the 26th Regiment did not get the message until too late, and took even heavier casualties.

Like many of the Japanese plans from this campaign, the attack was overly ambitious. This overconfidence and lack of ability from the Japanese chain of command would lead, in September, to the total destruction of the Japanese force, and utter victory for the Soviets. Throughout this long battle, the Kaenbin would serve where possible. Today, Nomnhan/Khalkhin-Gol is largely overshadowed by the Second World War, which started just as the battles were winding down.

In the Pacific

The Kaenbin or some other variant of the idea would see service in the latter part of the Second World War. Once again, the Japanese would face a superior armored force in the shape of the Allies. A standard part of the Japanese anti-tank tactics was the Kaenbin. Japanese anti-tank tactics called for an ambush, preferably where terrain limits the mobility of the tank and slows it down. In an ideal engagement, the tanks supporting infantry would be pinned, or forced to withdraw. Then the tank would be immobilized by mines, or whatever was on hand. Then the crew of the tank would be forced to dismount. One such tactic suggested for this was to attack the tank with Kaenbin, although other weapons, such as the Type TB gas grenade could be used.

Japanese soldiers attack a M3 Stuart tank with a Kaenbin, or similar device. From the quality of the picture, and the utter lack of covering fire against an exposed enemy, it suggests that this is a propaganda picture.

With the tank unmanned and immobilized, it could be destroyed, or booby-trapped at leisure by engineers. Of course, if it was the only weapon the Japanese infantryman had, he would go straight to the attack with the Kaenbin, although success was unlikely. Even in the last days of the fighting at Nomonhan, the Japanese reported that Russian tanks had tarpaulins draped over their rear decks to render the Kaenbin ineffective.

Sources

Drea, E. J. (1981), Leavenworth Papers: Nomonhan. Fort Leavenworth: Combat Studies Institute.URL: https://apps.dtic.mil/dtic/tr/fulltext/u2/a322749.pdf (accessed 1/1/2021)
Coox, A. D. (1985), Nomonhan: Japan Against Russia, 1939. Stanford: Stanford University Press.ISBN: 0804718350.
Japanese tank and Anti-tank warfare (1945) Washington: United States Government Printing Office. Series #34. URL: http://www.easy39th.com/files/Special_Series,_No._34_Japanese_Tank_and_Antitank_Warfare_1945.pdf (accessed 1/1/2021)
Taki’s Home Page (2004) Imperial Japanese Army Page Available at: http://www3.plala.or.jp/takihome/ (accessed 1/1/2021)

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Sticky and Magnetic Anti-Tank Weapons

Infantry taking on tanks is a real challenge. Infantrymen are, after all, mainly equipped with weapons primarily intended for killing enemy infantry. Anti-tank guns are large, cumbersome, and heavy and so, right from the first days of the tank in WWI, the goal has been to produce a man-portable anti-tank weapon. One of the first, the Mauser Panzergewehr M1918 was little more than a scaled-up rifle designed to defeat relatively modest armor. More anti-tank rifles followed in the decades afterward up to the first years of WW2, but they all suffered from the same drawbacks. The rifles were so large and heavy they would take at least one (often two) men to carry without being able to carry the usual accouterments of infantry work. On top of this, the performance was relatively modest. Only thinly armored vehicles were vulnerable and anything with armor about 30 mm thick was relatively impervious to them.

Smaller devices, the sort of device which could be issued to a standard soldier making him capable of knocking out a standard enemy tank were, and still are, the gold standard for infantry anti-tank weapons. Grenades, small explosive devices, were useful but were primarily to spray fragments over an area to target infantry. Their effect was relatively limited against armored vehicles unless you could get the explosives in direct contact with the tank and one way to do this was to make the explosive ‘stick’ to the vehicle. Tanks, being made of steel, lent themselves to an obvious thought, why not make the explosive charge magnetic?

Here, there are two distinguishing elements: throwing and placing. Grenades, as throwing weapons, are advantageous for the soldier as they permit the user to maintain a distance from the target. The smaller and lighter (to a point) the grenade, the further it can be thrown. This also means that the features of an effective grenade against armor are also challenged. The size of the charge used is inherently going to be small with larger charges being harder to throw and therefore of shorter range. The next is accuracy, the further an item being thrown, the lesser the chance of hitting the target. Of course, a smaller grenade is also easier to carry and deploy.

A charge, on the other hand, such as an attachable mine, has to be placed on the target. This allows for the significant advantage of a large charge, shaped if possible to optimize anti-armor performance, but which would not lend itself to being thrown. A further advantage of the placed charge is also the obvious one, it guarantees a ‘hit’ because it does not have to be thrown and risk hitting and bouncing off the target. The disadvantages are equally obvious; the man has to expose himself to enemy fire to place the charge, has to be uncomfortably close to the enemy tank, and they are also larger and heavier than a grenade to contain enough explosives to do effective damage, meaning fewer of them can be carried.

All of the various attempts to develop either a hand-placed charge or thrown charge suffered from these problems and none adequately managed to overcome them.

Development

Such a relatively simple idea, though, was far easier to imagine than it was to turn into a functional weapon. Some experience in the area could be drawn from naval warfare. There, a magnetically attached charge had been developed by the British as a means of sabotaging enemy ships: the Limpet mine. A relatively small explosive device, adhering to the steel of a ship’s hull could burst a seam or plate and cause enough damage to put it out of action until it was patched. The power of the charge was magnified if it was placed below the waterline, as the pressure of the water helped to magnify the explosive power of the charge and, obviously, a hole above the waterline was less useful at crippling a ship.

Britain

For the British, the work on the underwater anti-ship charges found its way both in style and name to a land weapon. The ‘Clam’, as it was called, originally came with a light steel body (Mk.I), later replaced with a Bakelite (plastic) body (Mk.II) with four small iron magnets, one in each corner. Resembling a large bar of chocolate, this charge contained a modest charge of just 227 grams of explosive. This charge was a 50:50 mix of Cyclonite and T.N.T. or 55% T.N.T. with 45% Tetryl. Although the device was magnetic, the charge was not shaped nor specifically designed for breaching armor plate. The utility of the mine was for sabotage. Enemy infrastructure, vehicles, railway lines, and storage tanks made excellent targets for this mine. The ‘Clam’ was able to breach just 25 mm of armor, offering little compared to far simpler anti-tank weapons such as the No.82 ‘Gammon’ bomb or No.73 Grenade, aka the ‘Thermos Bomb’. Both of these were weapons that could be thrown from a safe distance, exploded on impact, and were far simpler to make.


The British No. 82 and No. 73 Anti-Tank Grenades. British Explosive Ordnance, 1946

The ‘Clam’, therefore, found a role in sabotage, where it was very effective. Large quantities were produced in Britain and shipped to the Soviet Union for exactly that purpose.

The British ‘Clam’ and Limpet Magnetic charges. The circular Limpet (Mk.III) used a ring of magnets in a flexible fitting allowing for fitting to a contoured surface and capable of breaching 60 mm of steel plate. Source: Wikimedia Commons

The most famous, or infamous, Anti-Tank Grenade is probably the British ‘sticky bomb’. Although not magnetic, the ‘sticky bomb’, officially known as the ‘No.74 S.T. Mk.1 HE’, was constructed from a glass sphere containing 567 grams of nitro-glycerine and covered with a stockinette fabric to which an adhesive was applied. Once the protective steel shells around the grenade had been removed, it could be thrown at an enemy tank. When the bulbous glass ball at the end struck the tank, it would break causing the nitro-glycerine inside to ‘cow-pat’ on the armor and remain stuck there by the glued stockinet until it was detonated. The weapon was not a success, but was also made in large numbers and saw service in North Africa and Italy against German and Italian forces.

The No.74 S.T. Mk.1 HE ‘Sticky Bomb’. Source: British Explosive Ordnance, 1946

Video of a British No.74 Grenade being demonstrated rather badly by American forces in Italy 1944. The thrower did not manage to break the glass bulb, resulting in it falling off before it exploded.

German Weapons

Probably, the most famous magnetic anti-tank device was the German Hafthohlladung (handheld hollow charge). These came in different sizes, although the most common weighed in at 3 kg. This Hafthohlladung mine used three large magnetic feet to adhere to the armor of a vehicle. Each permanent horseshoe-shaped magnetic foot, made from Alnico-type alloy (VDR.546) had an adhesion strength of 6.8 kg-equivalent, meaning over 20 kg of force-equivalent would have to be used to remove a well-adhered mine and also that only a single foot was needed to ‘stick’ the mine to a steel surface. The 3 kg Hafthohlladung contained a simple 1.5 kg shaped charge consisting of PETN/Wax.

A still from a German wartime training film showing the correct method of use of a Hafthohlladung mine against the side of a Soviet T-34 tank. Source: Wikimedia Commons

Placed by hand on the target, the position of the magnets ensured that the shaped charge, when detonated, would strike the armor perpendicularly and at an optimal stand-off distance to maximize its anti-armor potential. According to British tests in 1943, the 3 kg charge could perforate up to 110 mm of I.T. 80 D armor plate or 20 inches of concrete, meaning that it could defeat any Allied tank then in service almost regardless of where it might be placed.

A later, and slightly heavier model of this mine weighing 3.5 kg contained up to 1.7 kg of 40% FpO2 and 60% Hexogen explosive which was capable of defeating over 140 mm of armor. A post-war British report stated that versions of this type of grenade were known in 2, 3, 5, 8, and even 10 kg versions.


3.5 kg bell-shaped variant of the Hafthohlladung, and (right) alongside the conical 3 kg Hafthohlladung. This version used the projectile from the Panzerfaust 30. Source: lexpev.nl

A German soldier in spring 1944 prepares himself for the run out of cover to place a Hafthohlladung on a target either during training or on the Eastern Front. Such a run from cover exposed the user to enemy fire. Source: Bundesarchiv.
An extremely nervous-looking German soldier making a mess of applying a Hafthohlladung against the suspension of a captured French Renault R35 during training. Considering the mine is capable of piercing the armor at any place, it is wholly unclear what he is trying to achieve. Source: Wikimedia Commons

An even larger version of the Hafthohlladung was made for the German Luftwaffe, known as the Panzerhandmine (P.H.M.), or sometimes as the Haft-H (L) ‘Hafthohlladung-Luftwaffe’. This device had the appearance of a small wine bottle with the base cut off to make room for six small magnets. Larger than the Hafthohlladung, the P.H.M.3 still had to be applied by hand.


German Panzerhandmine. Source: TM9-1985-2 German Explosive Ordnance and Intelligence Bulletin May 1945

A small, spiked steel ring was fixed to the bottom of the magnets so that the charge could be stabbed onto a wooden surface too. In order to fasten to a steel surface, all that was required was the removal of this ring. First appearing in about 1942, the P.M.H.3 (a 3 kg version) contained a shaped charge made from 1.06 kg of T.N.T. or a 50:50 Cyclonite/T.N.T. mix. Against a steel target, this charge was sufficient to pierce up to 130 mm, making it a very serious threat against a tank. A 4 kg version (P.H.M.4) was also developed with a performance of up to 150 mm, although details are very limited.

A Hafthohlladung being attached to the back of a tank after having passed over the trench. Showing a Russian soldier, this image illustrates a far safer means of attaching the mine to a tank, obviating the need to stand alongside the vehicle. Even so, the soldier needs a heart of steel to be this close and is still exposed to enemy troops following the tank. Source: Fedoseyev via survincity


German ‘sticky’ shaped charge – the Panzerhandmine S.S.. Details of this version are scarce. Source: Tech. Report No.2/46

A variant of this mine also had a sticky ‘foot’ with different mixtures of explosive compositions. The sticky versions had the advantage of being able to stick to any solid surface regardless of whether it was magnetic or not. In this way, it was emulating the British idea of an adhesive-impregnated fabric behind a thin steel cover. Containing a 205 gram filling of 50% RDX and 50 % TNT, the entire charge weighed just 418 grams, just over a pound. Able to penetrate an I.T. 80 homogenous steel plate 125 mm thick, this small mine was a very effective weapon in terms of penetration although how many were made or used is unknown. A further variation of this grenade allowed it to be thrown, relying on the stickiness to attach to the armor with an instant fuse and small streamer behind to ensure it landed sticky-side down. No other details are known.

Thrown version of the hollow charge German sticky grenade. Source: and Tech. Report No.2/46

Another variation for a hand-placed sticky charge from the Germans was more complex than just an adhesive-impregnated fabric. This version featured the same sort of thin protective cover but with the detonator as part of the sticky process. Here, once the detonator was pulled, it would create an exothermic reaction melting the plastic on the face to make it ‘sticky’. It was, at this point ‘live’, so had to be applied or discarded as it would then blow up. No known use of this particular device or live examples are known.

German handheld Haftmine featured a usual self-melting element allowing it to stick to any hard surface regardless of whether it was magnetic or not. Source: Federoff & Sheffield

One further German magnetic charge was the 3 kg Gebalte Ledung (Eng: Concentrated charge) demolition charge which was little more than a large box with magnetic panels on each side. The interior was filled with cubes of explosives and had the additional advantage of being throwable. Even if the magnets failed to adhere to the steel of the tank, the 3 kg charge was sufficient to cause a lot of damage and possibly cripple the vehicle. However, as it was not a shaped charge, the anti-armor performance was relatively poor. Even so, it was more than capable of knocking out the Soviet T-34 and capable of sticking on the target even when thrown, but few other details were known.

German 3 kg demolition slab ‘Geballte Ladung’ with magnetic plates at each end, fitted with the B.Z.39. Friction Igniter. Source: Department of Tank Design

Many of these German shaped charge devices were made by the firm of Krümmel Fabrik, Dynamite AG which, after a lot of trials, found that the best mix for shaped charges was the explosive Cyclotol which was made up of 60% Cyclonite and 40 % T.N.T. with other mixtures producing less efficient results. Under ideal conditions, they found that a 3 kg shaped charge with this explosive could penetrate up to 250 mm of armor, although ideal conditions were rarely to be found on the battlefield. Either way and despite numerous attempts at both magnetic and ‘sticky’ anti-tank weapons, the Germans did not deploy them in significant numbers. One British report of late 1944 even confirmed that they had, to that point, yet to confirm that even a single Allied tank had been knocked out by a magnetic mine, the far bigger threat being the German ‘bazooka’, the Panzerfaust.

Japan

The Japanese, like the Germans and to a lesser extent, the British, had experimented with magnetic anti-tank weapons. Unlike both of them though, Japan was successful. The primary magnetic anti-tank weapon was the deceptively simple Model 99 Hakobakurai ‘Turtle’ mine. Reminiscent in shape to a turtle with four magnets sticking out like feet and the detonator looking like the head, this canvas-covered circular mine was a potent threat to Allied tanks in the Pacific theater of operations.


Japanese Type 99 Hakobakurai anti-tank mine. Source: TM9-1985-4

Appearing on the battlefield from 1943 onwards, the Hakobakurai weighed just over 1.2 kg and was filled with 0.74 kg of cast blocks of Cyclonite/T.N.T. arranged in a circle. Placed against thin points of armor or on the hatch of a tank, this mine, when detonated, could penetrate 20 mm of steel plate. With one mine on top of another, this could be increased to 30 mm, although, depending on the armor it was on, it could cause damage to a plate thicker than that.

The mine was not a shaped charge and 20 or even 30 mm of armor penetration was not much use against anything but the lightest of Allied tanks deployed against the Japanese, such as the M3 Stuart, unless they were placed in a vulnerable spot such as underneath, on the rear, or over a hatch. However, British testing and examination of these mines reported that, although the penetration was poor, just 20 mm, the shockwave from the blast could scab off the inner face of an armor plate up to 50 mm thick, although the penetration was still limited by it not being a shaped charge. The result also did not include vehicles designed with an inner ‘skin’ either, but the results were still substantial, as it meant that all of the Allied tanks used in the Pacific theatre were vulnerable to these mines depending on where they were placed.

A further development of it, known as the ‘Kyuchake Bakurai’, was rumored and capable of being thrown up to 10 yards (9.1 m), although as of October 1944, no examples were known to have been found.

The Japanese had, from about May 1942, obtained shaped charge technology from the Germans and the results were first recorded by the Americans following combat in New Guinea in August 1944. Here, they reported finding a Japanese shaped charge weapon shaped like a bottle and fitted with a magnetized base, very similar in description of the German Panzerhandmine. As of October 1944 though, the British, aware of this weapon, still had not encountered any:

“Although there are no details of Japanese hollow charge magnetic grenade it is highly probable that such weapons will be encountered soon”
D.T.D. Report M.6411A/4 No.1, October 1944

Scab blasted off from the inside of a 1 ½” (38 mm) thick armor plate by a Japanese Model 99 Hakobakurai ‘Turtle’ mine. Source: Department of Tank Design
Scarring on the outside (left) of a 2” (51 mm) thick armor plate and partially detached scab on the inside (right) caused by the detonation of at least 1 Model 99 mine. Note that the blast has dented the armor and the shape of the individual blocks can even be made out. The gaps between the blocks acted like miniature shaped charges causing these deep scars. Source: Department of Tank Design

Italy

The Kingdom of Italy, perhaps contrary to common ‘knowledge’, also made use of two devices of note. The first of these was a close copy of the British No.74 S.T. Mk.1 HE grenade reproduced from examples captured from the British in North Africa. The Italian version, known as the Model 42 grenade, was manufactured in limited numbers by the firms of Breda and OTO but, importantly, was not sticky. The Italians simply copied the large spherical explosive charge and omitted the not-so-reliable sticky stockinette and glass bulb part of the design. One important note on a heavy grenade like this is the range, just 10-15 meters at best.


The 1 kg Model 42 Grenade contained 574 grams of plastic explosive but was not sticky, it simply emulated the shape of the British No.74. Source: Talpo.it

Although the Model 42 was neither sticky nor magnetic, the Italians did develop probably the most advanced man-portable magnetic anti-tank weapon of all. Here though, there is very little to go off. Just a single photograph is known of the device consisting of a small battery pack and charge on a simple frame. The mine is relatively small, perhaps only 30 cm wide and appears to consist of a bell-shaped central charge, almost certainly a shaped charge with a rectangular battery and two large electromagnets on the ends of the steel frame. Certainly, this would have some advantages as it would not be magnetic all the time, unlike the German Hafthohlladung. It was simply placed on a tank and the switch was flicked to activate the battery and the powerful electro-magnets would hold the charge in place until it detonated. At least one prototype was made in 1943 but, with the collapse of Italy in September 1943, all development is believed to have ceased.

The experimental Italian electromagnetic anti-tank mine. Source: Cappellano and Pignato

Yugoslavia

Perhaps even more obscure than the Italian work on the subject of magnetic weapons is a single known Yugoslavian example. Known as the Mina Prilepka Probojna (Eng: Mine Sticking Puncturing), it was developed after the war and was intended for disabling non-combat and light combat vehicles rather than main battle tanks. It could also be deployed in the manner of the ‘Clam’ for sabotage purposes on infrastructure and consisted of a cylinder with a cone on top containing a 270-gram Hexotol shaped charge and was capable of piercing up to 100 mm of armor plate. Packed 20 to a crate, the MPP was a potent small mine but there is little information available on it in general outside of a small manual of arms. How many were made and whether it was ever used or not is not known.


The Post-War Yugoslavian Mina Prilepka Probojna magnetic mine. Source: Yugoslavian Arms Manual (unknown)

Conclusion

None of the attempts to produce a smaller anti-tank explosive weapon using either sticky or magnetic principles were shown to be effective. The magnetic charges required the soldier to be often suicidally close to the enemy tank. The sticky-option permitted the chance to be further away and possibly have the grenade hopefully strike the vehicle where the charge could perforate the armor. Many other ideas for hand-thrown anti-tank weapons were fielded by various armies in WW2 and thereafter, such as an attempt at a top attack hollow charge similar to that German Panzerhandmine S.S., but none were particularly successful. A short-range, inconsistent effect and a huge question over accuracy were not the reasons these devices do not appear in today’s army’s arsenals though. The answer is that far simpler, more reliable, and more effective systems became available. The German Panzerfaust had, by the end of the war, reached a level of performance where a soldier could be up to 250 meters from a target and perforate up to 200 mm of armor. The modern rocket-propelled grenade (RPG) really embodies this change in military thought for anti-armor weapons and appears in multiple forms for decades, providing an enormous punch for the average soldier against armor.


Examples of when the attack with a magnetic mine has failed. Here wedged into the screen over an air intake (left), and attached to the Schurzen (right) on a StuG III Ausf. G of 2nd Assault Gun Detachment, Bulgarian Army, after combat in Yugoslavia, October 1944. Source: Matev

References

Hills, A. (2020). British Zimmerit: Anti-Magnetic and Camouflage Coatings 1944-1947. FWD Publishing, USA
British Explosive Ordnance, US Department of the Army. June 1946
Federoff, B. & Sheffield, O. (1975). Encyclopedia of Explosives and Related Items Volume 7. US Army Research and Development Command, New Jersey, USA
Fedoseyev, S. Infantry against tanks. Arms and Armour Magazine retrieved from http://survincity.com/2011/11/hand-held-antitank-grenade-since-the-second-world/
Hafthohlladung https://www.lexpev.nl/grenades/europe/germany/hafthohlladung33kilo.html
Technical and Tactical Trends Bulletin No.59, 7th March 1944
TM9-1985-2. (1953). German Explosive Ordnance
Matev, K. (2014). The Armoured Forces of the Bulgarian Army 1936-45. Helion and Company.
Cappellano, F., & Pignato, N. (2008). Andare Contro I Carri Armati. Gaspari Editore
Department of Tank Design. (1944). The Protection of AFVs from Magnetic Grenades
Grenades, mines and boobytraps, retrieved from www.lexpev.nl/grendades/europe/germany/panzerhandmine3magnetic.html
Guardia Nazionale Repubblicana. (1944). Istruzione sulle Bombe a Mano E Loro Impiego
Armaments Design Department. (1946). Technical Report No.2/46 Part N.: German Ammunition – A Survey of Wartime Development – Grenades.