WWII British Tank Guns and High Explosive Shells

Started reading about British tanks during WWII and one of the main failings of the domestic models seems to of been a distinct lack of a high explosive shell. Now that appears to have been thanks to a combination of armoured doctrine saying that tanks are for mostly combating other tanks, the Royal Artillery being a bit arsey and operating on the assumption that any high explosive shells should be coming out of their guns, and some puzzling institutional slowness on developing new marks of equipment. All of which meant they had great shells against tanks, but against anti-tank guns and infantry where you need a good high explosive one they were kind of a bit buggered. So can someone confirm my initial reading of things? Thanks.

  • 2-pounder (39mm) gun: More than enough against any enemy tanks it was likely to meet in the early stages of the war, against 88mm Flak guns horribly outranged roughly 5:1, whilst high explosive shell designed never put into production and would probably of been too small to really be effective anyway.
  • 6-pounder (57mm) gun: Somewhat of an improvement, started out mainly as an anti-tank gun - and even then had a fair bit of useless delays - but provided decent service on tanks, able to penetrate enemy tanks of the time and finally a high explosive shell issued but not all that great as shell was too small, only outranged 10:1 by an 88mm gun.
  • 75mm Medium Velocity (MV) gun: American, used on M3s as a hull mounted gun or M4s as the main turret gun, excellent high explosive shell - possibly best of the war for the Allies, medium rather than high velocity made it good for high explosive but not so great for anti-tank work due to lower velocity, still capable of taking out anything until the Tigers showed up though, outranged by an 88mm gun roughly 8:1.
  • 17-pounder (76.2mm) / 77mm High Velocity (HV) gun: Now we're cook with gas, originally started as an anti-tank gun but converted to fit into tanks, originally developed to fire the 75mm shells at a higher velocity but changes meant regular 17-pounder and 77mm HV shells weren't interchangeable - hence the name, excellent anti-tank capability thanks to high velocity but also means less great with high explosive shells due to both high velocity and resultant shell design, high explosive shell issued at the beginning considered fairly rubbish, not fixed until Mk II version, outranged by an 88mm only 7.5:1 - whoo! ;)
Now for the 17-pounder/77mm the high velocity meant that they had to build up and strengthen the walls of the high explosive shells leaving less space for the explosive itself, this being solved by taking the seemingly obvious step of simply reducing the charge in the MK II version so that it had a lower velocity and allowed thinner-walled shells. Unfortunately it didn't happen until 1944 or work through to units in combat until 1945. There was also the factor that the UK apparently used cheaper steel to make their shells so had a poorer charge/weight ration than compared to US ones. Does anyone know why the obvious solution of simply reducing the charge for the 77mm high explosive shell to make it lower velocity wasn't introduced much sooner? The whole story of British tank development seems to be one of missed opportunities and on the face of them rather puzzling delays, once I've finished a bit of reading probably going to start looking at how things could of possibly been nudged along with the fewest and smallest possible points of departure.
 
I've got a sneaking suspision you're comparing absolute maximum ballistic range (i.e. lands somewhere over thataway) for the 88 with the effective ranges (i.e. get decent accuracy and penetration out that far) of the others...
 
Generally speaking you're right, but I don't know where you're getting your range figures from since they seem frankly bizarre. Wikipedia lists the 88mm PaK 43 as having an effective range of 4km, while the 6-pdr https://en.wikipedia.org/wiki/Ordnance_QF_2_pounder has an effective range of 1.5km. It is not outranged by a factor of 10, as you claim! If you were looking at the flak version of the 88, keep in mind that the maximum range figure quoted there is probably for indirect fire, not the direct fire that would be used in the AT role.

I'd suggest that the 88mm is not an appropriate comparison in any case, since they were rather less common than anecdotes suggest and AFAIK were never the main AT firepower of the German army. The PaK 38 seems a more reasonable yardstick to use, or perhaps the PaK 40.
 
Whoops. That's what you get for asking questions before finishing the book. :) Well that and using the Genocide. I was mainly using the 88 as a rough comparison since for the first half of the war that seemed, anecdotally, to be what gave the British forces in Africa the most problems. Ignoring that though the main bit seems roughly right? Still wondering about the 77mm Mk II shell, may have to go have a poke around some of the tankhead sites.
 
I was mainly using the 88 as a rough comparison since for the first half of the war that seemed, anecdotally, to be what gave the British forces in Africa the most problems.

Anecdotally every gun was an 88, every tank was a Tiger, and so on. It pays to take that sort of evidence with a grain of salt - it's not necessarily inaccurate, but you might want a bit of corroboration before deciding what to make of it.
In actual fact, I suspect it was the afore-mentioned PaK 38 that was responsible for a good many of the British tank casualties in Northern Africa. The Afrika Korps was willing to use them quite aggressively, including to bolster the firepower of their tanks when on the offensive, and since they were hard to see it's likely that many of their kills were attributed to other factors such as panzers and the 88. Just my $0.02 worth, but I can recommend "World War II Desert Tactics" by Paddy Griffith on that subject. It's part of the Osprey line of publications, and although not a particularly weighty tome it gives a good overview.

Returning briefly to the subject of range figures, that's another set of data it pays to be a bit sceptical about. Published figures are usually based on what the gun could achieve on a firing range - under the best possible conditions, in other words - and do not reflect what happens in combat. Case in point: during Operation Battleaxe, the British attacked Halfaya Pass and were disturbed when an entire tank squadron was destroyed at the impossibly long range of 1500 yards. It's also surprisingly hard to get a field of fire that can make use of all that theoretical range performance. Next time you go outside a town, take a look at the terrain and see how close a tank might be able to get before it had to break cover. It shouldn't be a surprise that most WW2 engagements took place at well under 2km, and often less than 1km.
 
Tanks are to support infantry so HE is what the army wants which is why the ROF 6 pounder had the barrel enlarged to take US 75mm shells despite that resulting in a worse armour piercing ability. In Italy 6 pounders were kept in some tanks to allow them to cope with German tanks.

The 2 pounder was effective against any German or Italian armour until well into 1941 and most into 1942. What it could not do is engage anti tank guns with high explosive. There is a story that high explosive rounds were made for the 2 pounder and sent to the Middle East. Sadly, in a well meaning effort to boost the explosive capacity the warheads were much longer so they did not fit into the tank stowage so were not issued. I have been told by my Yeomanry predecessors that post war they carried a few Littlejohn rounds but mostly squeezed these high explosive rounds in somehow in their Daimler armoured cars as there were few situations armour piercing rounds could solve but many the high explosive could.

When the 6 pounder came in it could do both but the army needed even better high explosive performance to deal with dug in positions in order to support infantry. Hence they sacrificed the anti tank performance with the enlargement to 75mm. The 6 pounder could have come in much earlier but anti tank guns and UK defence were the priority. As a 2 pounder could take out any German tank in 1940 the decision was made for many 2 pounders now rather than some 6 pounders later. In the face of invasion the correct decision but tank crews paid dearly for that later.

The 6 pounder, with armour piercing discarding sabot rounds, remained a viable anti tank weapon until the end of the war even if a 17 pounder was better. I have spoken with a Ukrainian Soviet Army Valentine tank commander and he was adamant that (even with the normal anti tank rounds, his Valentine could cope with Panzer IVs (and was small and quiet enough to creep around Tigers and Panthers for side and rear shots).

The intention had been to replace the 6 pounder with a high velocity 75mm from Vickers. I have been told that Vickers designed it for an external mantlet (trunnions on the outside like a Sherman) but the turret designers designed an internal mantlet so the gun would not fit Cavalier/Cromwell or Churchill turrets so they were forced to use the ROF medium velocity 75mm.

I cannot comment upon the qualitative difference between US and British high explosive warheads but I do know that US 57mm anti tank gunners would give much kit to get British 6 pounder high explosive rounds in unofficial deals. Also the first Grants in the Middle East had their 75mm US rounds replaced with hybrid ones made of captured German 75mm warheads and captured French 75mm artillery cases.

One reason behind a difference in high explosive guns between the USA and UK was doctrine. In that UK tanks, despite the Infantry/Cruiser split, were expected to engage enemy tanks. The USA doctrine was that tank destroyers engaged enemy tanks while tanks only supported infantry so they had better anti tank guns on larger lightweight turrets on the tank destroyers and better high explosive guns in smaller armoured turrets on the tanks.

It would have been so much easier had there been HESH rounds. One rounds does all. Challenger 120mm HESH rounds took out Iraqi tanks from kilometres away and 76mm Kuwaiti Saladins did take out a few Iraqi T55s.

Given hindsight and existing technology I have, elsewhere postulated that the Valentine could have been the standard and only tank for the British Army by the beginning of the war in 1939 and could have been made in quantity and kept upgraded to be useable up to 1944 when it could have been replaced by a something like a Centurion with a 17 pounder.
 

Sior

Banned
Tanks are to support infantry so HE is what the army wants which is why the ROF 6 pounder had the barrel enlarged to take US 75mm shells despite that resulting in a worse armour piercing ability. In Italy 6 pounders were kept in some tanks to allow them to cope with German tanks.

The 2 pounder was effective against any German or Italian armour until well into 1941 and most into 1942. What it could not do is engage anti tank guns with high explosive. There is a story that high explosive rounds were made for the 2 pounder and sent to the Middle East. Sadly, in a well meaning effort to boost the explosive capacity the warheads were much longer so they did not fit into the tank stowage so were not issued. I have been told by my Yeomanry predecessors that post war they carried a few Littlejohn rounds but mostly squeezed these high explosive rounds in somehow in their Daimler armoured cars as there were few situations armour piercing rounds could solve but many the high explosive could.

When the 6 pounder came in it could do both but the army needed even better high explosive performance to deal with dug in positions in order to support infantry. Hence they sacrificed the anti tank performance with the enlargement to 75mm. The 6 pounder could have come in much earlier but anti tank guns and UK defence were the priority. As a 2 pounder could take out any German tank in 1940 the decision was made for many 2 pounders now rather than some 6 pounders later. In the face of invasion the correct decision but tank crews paid dearly for that later.

The 6 pounder, with armour piercing discarding sabot rounds, remained a viable anti tank weapon until the end of the war even if a 17 pounder was better. I have spoken with a Ukrainian Soviet Army Valentine tank commander and he was adamant that (even with the normal anti tank rounds, his Valentine could cope with Panzer IVs (and was small and quiet enough to creep around Tigers and Panthers for side and rear shots).

The intention had been to replace the 6 pounder with a high velocity 75mm from Vickers. I have been told that Vickers designed it for an external mantlet (trunnions on the outside like a Sherman) but the turret designers designed an internal mantlet so the gun would not fit Cavalier/Cromwell or Churchill turrets so they were forced to use the ROF medium velocity 75mm.

I cannot comment upon the qualitative difference between US and British high explosive warheads but I do know that US 57mm anti tank gunners would give much kit to get British 6 pounder high explosive rounds in unofficial deals. Also the first Grants in the Middle East had their 75mm US rounds replaced with hybrid ones made of captured German 75mm warheads and captured French 75mm artillery cases.

One reason behind a difference in high explosive guns between the USA and UK was doctrine. In that UK tanks, despite the Infantry/Cruiser split, were expected to engage enemy tanks. The USA doctrine was that tank destroyers engaged enemy tanks while tanks only supported infantry so they had better anti tank guns on larger lightweight turrets on the tank destroyers and better high explosive guns in smaller armoured turrets on the tanks.

It would have been so much easier had there been HESH rounds. One rounds does all. Challenger 120mm HESH rounds took out Iraqi tanks from kilometres away and 76mm Kuwaiti Saladins did take out a few Iraqi T55s.

Given hindsight and existing technology I have, elsewhere postulated that the Valentine could have been the standard and only tank for the British Army by the beginning of the war in 1939 and could have been made in quantity and kept upgraded to be useable up to 1944 when it could have been replaced by a something like a Centurion with a 17 pounder.

HESH was developed by Charles Dennistoun Burney in the 1940s for the British war effort, originally as an anti-fortification "wallbuster" munition for use against concrete. He also led British developments in recoilless rifles as a means to deliver the shell. An early application of the HESH principle was the Royal Engineers AVRE's 165mm demolition gun.

http://en.wikipedia.org/wiki/High-explosive_squash_head
 

hipper

Banned
  • 2-pounder (39mm) gun: More than enough against any enemy tanks it was likely to meet in the early stages of the war, against 88mm Flak guns horribly outranged roughly 5:1, whilst high explosive shell designed never put into production and would probably of been too small to really be effective anyway.
  • 6-pounder (57mm) gun: Somewhat of an improvement, started out mainly as an anti-tank gun - and even then had a fair bit of useless delays - but provided decent service on tanks, able to penetrate enemy tanks of the time and finally a high explosive shell issued but not all that great as shell was too small, only outranged 10:1 by an 88mm gun.
  • 75mm Medium Velocity (MV) gun: American, used on M3s as a hull mounted gun or M4s as the main turret gun, excellent high explosive shell - possibly best of the war for the Allies, medium rather than high velocity made it good for high explosive but not so great for anti-tank work due to lower velocity, still capable of taking out anything until the Tigers showed up though, outranged by an 88mm gun roughly 8:1.
  • 17-pounder (76.2mm) / 77mm High Velocity (HV) gun: Now we're cook with gas, originally started as an anti-tank gun but converted to fit into tanks, originally developed to fire the 75mm shells at a higher velocity but changes meant regular 17-pounder and 77mm HV shells weren't interchangeable - hence the name, excellent anti-tank capability thanks to high velocity but also means less great with high explosive shells due to both high velocity and resultant shell design, high explosive shell issued at the beginning considered fairly rubbish, not fixed until Mk II version, outranged by an 88mm only 7.5:1 - whoo! ;)
.


the 2 lber started the war with a small high explosive content of about 18 grams designed to have a small explosive incendiary effect after it had penetrated an ememy tank

this was then replaced with a solid shell with slightly improved armour penetraton characteristics. About 4mm at 500 yds IRRC.

finally a proper HE shell was designed for the 2 lber in 42 or 43

I'm not aware of any "long HE shells which could not fit in the rack of a british tank though there are some internet rumours stating this, if anyone has some real data on this topic let me know.

If you wanted to improve british tanks

a) give them a capped AP round in late 1941 which could take on the extra face hardened german armour added to their tanks about then,

b) fit a better gun than the 3" howitzer fitted to most british support tanks as a bomb thrower

c) have them expand the tank arm earlier and slower so that what skill and knowledge there was, was not so diluted in 1941.

Introduce production of the 6lber before Dunkirk.




cheers Hipper
 

Sior

Banned
the 2 lber started the war with a small high explosive content of about 18 grams designed to have a small explosive incendiary effect after it had penetrated an ememy tank

this was then replaced with a solid shell with slightly improved armour penetraton characteristics. About 4mm at 500 yds IRRC.

finally a proper HE shell was designed for the 2 lber in 42 or 43

I'm not aware of any "long HE shells which could not fit in the rack of a british tank though there are some internet rumours stating this, if anyone has some real data on this topic let me know.

If you wanted to improve british tanks

a) give them a capped AP round in late 1941 which could take on the extra face hardened german armour added to their tanks about then,

b) fit a better gun than the 3" howitzer fitted to most british support tanks as a bomb thrower

c) have them expand the tank arm earlier and slower so that what skill and knowledge there was, was not so diluted in 1941.

Introduce production of the 6lber before Dunkirk.




cheers Hipper

I think the confusion is over the Littlejohn adaptor for the 2pdr that required special rounds, a normal round through the adaptor could be interesting in a bad way!
http://en.wikipedia.org/wiki/Littlejohn_adaptor
 
I only know of the 'long' HE 2 pounder rounds from older ex members when I was in the Yeomanry and they told me that, in their Daimler armoured cars post war, they used Littlejohn rounds but without the adaptor as it made little difference at any range that made shooting at armour an alternative to running away. They had HE rounds and they were longer but an application of a Brummagen screwdriver judiciously got them to fit in the stowage.

I cannot imagine that they made new HE rounds post war so these would have been wartime production.

In the context of mid 1940 it would have been an error to stop 2 pounder production to introduce 6 pounders but the 6 pounder was designed well before the war so it could have been in service by 1940 but the army only had so much money to spend and the 2 pounder was one of the best anti tank guns until into 1941. Had they swapped to the 6 pounder pre war then something else would have been unbought. Technically there was no reason why the British army could not have gone to war in 6 pounder Valentine tanks.

When we look at the Italian/Israeli 60mm hyper velocity gun that went into Chilean Shermans in the 1980s one could wonder if the 6 pounder could have been developed further as a lighter weight anti tank gun instead of the 17 pounder but probably this needs modern steels etc.
 
The 6-pdr story by Peter Beale in 'Death by Design.


During the period when the two-pounder was being developed and mounted in tanks (as well as being used for ground-mounted anti-tank equipment), the thickness of armour on all tanks was rising steadily. There was clearly a case for a heavier gun. Col. Campbell Clarke was deputy Chairman of the Ordnance Board in 1937, and he had urged the then Director of Artillery, Maj Gen H. A. Lewis, to order a tank gun which could deal with tanks armoured to the 78mm standard of the Matilda. Lewis said that the General Staff did not consider it necessary. On 1 April 1938 Campbell Clarke succeeded Lewis as Director of Artillery, and on handing over Lewis said to Clarke, ‘Now you can get on with your gun’. Clarke proceeded to do just that.

The prime cause of this work was the field anti-tank gun rather than the tank gun; but from the start the possible future use of the gun in tanks was allowed for. Clarke called for general exploratory work on a six-pounder anti-tank gun in April 1938 ‘following generally the specification which governs the production of the two-pounder’. This request was made by the Design Department; but that department was understaffed and busy with other guns, and Clarke could not get General Staff priority.

Because of the shortage of design resources and the priorities given to them, designs for the six-pounder was not available until autumn 1939. The attention of the Director of Mechanisation, Maj Gen A.E. Davidson, responsible for the provision of tanks to the armoured forces, was drawn to the new gun at an early stage. But he was even less interested in a six-pounder tank gun than a six-pounder anti-tank gun; thus when a gun was available for trial in April 1940, and was approved, subject to testing, a tank and anti-tank gun, it was not specifically adopted for use in tanks.

In June 1940 the six-pounder passed its test at Shoeburyness. In July 1940 the Ministry of supply was asked to make fourteen pilot models, and in October they increased this to 50. At about this time Clarke read in an Ordnance Board minute that the Churchill tank currently being rushed through the design and manufacturing process was still to mount a two-pounder. Clarke protested vigorously to the Assistant Chief of the Imperial General Staff, Sir G.N. Macready and to his own boss, the Director General of Munitions Production, Sir Harold Brown. Clarke had already pointed out that the Germans, having investigated the Matildas left behind at Dunkirk, were very likely to increase the strength of both armour and the armament on their tanks – which they did.

Clarke also pressed the Director of Mechanisation to adopt the six-pounder in his tanks. Maj Gen Davidson pointed out that there was no General Staff requirement for a more powerful gun on tanks, and that ‘it was no part of the Director of Mechanisation’s duties to dictate to the General Staff when they had already decided their policies; the new Churchill tanks were designed to mount the two-pounder; and the size of the six-pounder would involve radical enlargement of the hull and turret’.

Macleod Ross records that: ‘On Clarke’s remonstrance Adm Sir Harold Brown (the DGMP) immediately ordered 2,000 six pounder anti-tank guns and 2,000 six-pounder tank guns. Unlike the D of M he did not care whether the General Staff approved or not, action which might be termed “the Nelson touch”.

The orders were there, but was the manufacturing capacity? Production was allowed to start only in a new factory at Radcliffe near Bolton because of War Office insistence that the production of two-pounders in existing factories should not be compromised.
 
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