An Pdr 75 Manual: Fill & Download for Free

Short Answer2 pounder HE rounds were not issued in the early part of the war to British tanksThey were issued to mid-war armoured carsThe reasons are not entirely clear, but the effectiveness of the 2 pdr gun in the HE role would have been low.The 2 pdr HE fill is 9.5% of the 75 mm HE shell as fired by the M3 Lee/Grant or M4 Sherman.Long AnswerHigh Explosive shells were issued for the 2 pdr later in the war when it became the standard armament for amoured cars. see Ian Holloway's answer to Was an HE round never made for the British 2 pounder gun, or was it just never deployed in the tanks that carried the weapon? Small HE rounds were useful against aircraft as we know from the successful 2 pdr pom-pom and Bofors guns- and similarly a 2 pdr HE would be useful against soft-skin vehicles and ground targets- albeit (see below) this would be largely in terms of the (important) morale effect- i.e suppressing the enemy.There is some debate about whether the British non issue of 2 pdr HE rounds was a pragmatic idea or one of doctrine- i.e “high explosive is for artillery, old chap”. I have not come across any explicit statement of this in my research, and it can be noted that some tanks did mount (rather ineffective) 3.7″ mortars in 1940- albeit these were mainly designed for firing smoke bombs.David Fletcher [Ref 1,] states the redoubtable Matilda 2 infantry tank was “not provided with a high explosive round, and even if one was available its explosive content would hardly have been worth considering”.Let us examine this further:Most of the criticism I have read about refers to the British Army’s experience in North Africa, when Matilda, Valentine and Crusader tanks find themselves out-ranged by Wehrmacht Heer anti-tank guns. When the M3 Lee/Grant tanks arrive from the US, their HE capacity (as well as high reliability) endeared them to the British tank crews.The tanks would have been up against 5 cm Pak 38 which were small and easy to conceal and 8.8 cm Flak 36 used in the A/T role- these were mainly used at long ranges and were accurate but hard to conceal.The performance of HE fire against anti-tank guns can be overestimated, however.Effectiveness of HE Fire on Anti-tank GunsWith respect to indirect artillery fire against dug-in antitank guns we have some operational research data [Ref 2] .Counter battery fire was carried out against German guns firing against Commonwealth units during Operation Veritable in 1945.3600 rounds of 80 lb 5.5″ fire landing in a 300 yard diameter area managed to knock out just 1 gun of a 5 gun battery. A second six-gun 8.8 cm battery was engaged with 5700 rounds landing in a 300 yard diameter circle. This savaging knocked out two guns! A bit better than the “Mad Minute” scene in Predator, but not much!Effectiveness of Small HE Rounds on Anti-tank GunsOk, let’s look at the effectiveness of small HE rounds such as that fired by the 2 pounderThe 2 pdr HE had a fill weight of 63 g. This is similar to a No. 36 Mills Grenade, slightly more than a modern 30 mm Bushmaster cannon HE round and quite a lot larger than the 32 g in an M406 40 mm low pressure rifle grenade- as used in Predator!The M406 has a quoted effective area of about 75 sq m =800 sq ft. [Ref 3]. This is against standing men, it would be rather less effective against the crouching crew of an anti-tank gun who would gain some protection from the gun shield.It should be noted that the effect of HE rounds is considerably moderated by terrain features [ Ref 4] and by simple trenches and sandbags. Advice to infantry- if you want to live-dig!The 2 pdr HE fill is 9.5% of the 75 mm HE shell as fired by the M3 Lee/Grant or M4 Sherman.Evaluations of small HE rounds were made during World War II: Ref 5Table 1: Calculated Vulnerable Areas of Small HE ShellsFor comparison, a 2 inch mortar round produced a vulnerable area of 1200 sq ft. Ref 6 assessed the effect of 2″ mortars as “negligible” against artillery.This assessment implies 2 pdr HE round would have been of dubious value against anti-tank guns in the Western desert.So what did the Germans and Americans do?According to Ref the German 37 mm Pak 36 gun did not have high explosive rounds either albeit they did existAn HE round for the US 37 mm gun was also provided [8]. Some commentators assessed it as “almost useless but Zaloga [9] states that in the Pacific Theatre they were useful for destroying bunkers and suppressing infantry with canister.Annex High Explosive Capacity of the 2 pdr HE round and US 37 mm2 PounderRef 10 gives the following data on the Shell HE/T Mk 2:Length of complete round: 17.577 inWeight of complete round: 4 lb 2 ozLength of projectile: 4.96 inWeight of projectile: 2 lb 6 ozFilling & Weight: RDW/BWX or TNT 2 oz 4.5 dr. (=0.14 lb= 63 g)Shell HE HV/T Mk is designed to replace Shell HE HV/T Mk2. The principles of construction are similar to those of the Mk2 shell, but fitted with the fuze DA No. 255. The trajectory of this projectile is similar to the APCBC shot up to 1,600 yards.US 37 mmThe 37mm HE round had 39 grams (0.085 lb) of TNT,way of contrast, the HE round from a Sherman 75 mm gun had 667 grams (1.47 lb) of TNT,ReferencesFletcher D (2017) British tanks of World War 2 page 46ORS2 (1945) report 29 Effect of Counter Battery Fire in Operation Veritable section c.Royal Military College of Science (1980) Handbook of Infantry WeaponsWO 291/138, Influence of ground cover on performance of HE projectilesWO 291/496, Anti-personnel effect of small HE shell.WO 291/538, A preliminary estimate of the destructiveness of various projectiles against Motor Transport and Artillery3.7 cm PaK 36"Complete Round Table for ammunition for 37mm guns (M63/TNT)". TM 9-1901 Artillery Ammunition, 1944. 1944. Retrieved 16 June 2018.Zaloga S J (2012) US Anti-tank Artillery 1941–45 Osprey p10"Ammunition Information Manual No.9" which is an official publication going into great detail about ammunition for the "Ordnance QF 2-pr Gun" (including the Littlejohns)

Short AnswerInformation on 2 pdr HE ammunition in the early part of the war is both confusing and contradictory.The balance of views is that an HE round was not deployed, albeit an APHE round was; this causes confusion.Assessment showed that a 2 pdr HE round would not have been an effective counter to German anti-tank guns even if it had been deployed in the Western Desert- albeit the morale effect of small HE rounds is hard to determine.An HE round was definitely produced and used in the latter part of the War, by which time the 2 pdr was relegated to use by armoured cars etc in the European theatre.Long Answer with detailed References which adds more information but no more clarity!The issues regarding the 2 pdr HE are very confusing. Some information is contradictory and a lot of the rest of the information is hard to substantiate from official documentation.The difficulties are exacerbated by:a.The parallel Naval 2 pdr pom-pom and 40 mm Bofors using HE rounds.b. The production of an APHE round for the 2 pdr that was referred to as the HE round. See Annex C.The Soviet Union looked at and the Australians produced a 2 pdr HE based on an AA shell, but I don’t think this is what the questioner is asking hereWas an HE Round Produced?It undoubtably was- see below, but was it available for the campaigns in France and the Western Desert?AGAINST A 2 pdr High Explosive being available 1939–42In reference 1, redoubtable author of the tomes I read in my youth Ian V Hogg states the HE round was never produced.David Fletcher [Ref 2,] states the redoubtable Matilda 2 infantry tank was “not provided with a high explosive round, and even if one was available its explosive content would hardly have been worth considering”Peter Chamberlin and Chris Ellis [Ref 3] say the HE round was not produced.Peter Gudgin [Ref 4] does not mention the HE round (or the APHE!)DiscussionIt is clear that, at the beginning of WWII British tanks were not designed to fire HE as can be seen from the choice of armament: the 2 pdr which would, at best fire a grenade sized HE shell or the 94 mm howitzer (a breech loading mortar really) which was optimized for lobbing smoke.The low velocity round from the 94 mm howitzer would be inaccurate against vertical targets at other than point-bank range whereas such a low-powered round enabled a decent amount of ammunition stowage for a tank designed around the 2 pdr. Smoke rounds don’t need to be too accurate. Records show than 0–4 HE rounds were carried for the 94 mm howitzer (e.g. for the tanks landed at Calais in 1940 [Ref 5].The British Army looks daft here, as they do not even provide an effective HE round for their Infantry tanks- designed to give fire support as they trundle with the troops . Of course, other countries armed tanks with similarly feeble weapons, but perhaps without such a clear mismatch between doctrine and armament.Some sources state that 2 pdr HE and 94 mm HE were not issued owing to the Royal Artillery wanting a monopoly on HE.For example the friendly The Miniatures Page site gives this information about the 2 pdr HE [Ref 6]:it was originally issued only to the artillery units equipped with the 2 pdr. Not to the tanks. This was in keeping with doctrine, which was that tanks were to close with the enemy, while artillery was expected to stand-off and shell the enemy in support. Even close-support tanks, which replaced the 2 pdr with 3-inch howitzers*, were originally issued with smoke to assist in closing with the enemy, rather than HE to assist in KILLING the enemy.[*The author means 3.7″ = 94mm howitzers here , these weapons were condemned as poor by David Fletcher [Ref 7]. They are not the same as the 95 mm howitzer mounted on Cavalier tanks in 1944.]Whilst not implausible I have not yet come across any firm evidence of this; rather the tanks were just not suitably armed for firing HE.Of course, that is not to say that the Royal Artillery background generals didn't have an influence on tank armament selection, albeit again, this is speculative.FOR A 2 pdr High Explosive being available 1939–42Tony Williams [Ref 8] states There was a 2 pdr HE round and it was issued to both anti-tank and tank regiments - until Dunkirk. After Dunkirk, it was decided to temporarily suspend HE production in order to build up stocks of AP shot against a German invasion, and, for some bureaucratic reason, this temporary suspension lasted until 1942, by which time the 2 pdr had ceased to be the main British AT gun.Alas, Mr Williams gives no authoritative source.So it is very doubtful if the round exists, and probable that there is a mix-up with the APHE round.The 2 pdr HE Round was issued!In spite of his apparant denial of its existence, Hogg in Ref 9 refers to a "Shell, HE Mk 2T" which was a pointed shell with a Base Percussion Fuze”In fact two types of HE are listed, plus an APHE. However things are only definitive for armoured cars in the second half of WWIIThe 2 pdr was the standard armament for Daimler, AEC and Marmington Herrington armoured cars, and these did have an HE Incendiary Tracer round, which had a mass of 1.86 lb and a bursting charge of 0.14 lb. David Boyd [Ref 10] gives these production figures, albeit without the mark of ammunition nor his original source for his information.Year No. 2 pdr HE Rounds Produced1942 …..40,0001943 ….. 474,0001944 …..384,000Annex A: Would a 2 pdr HE Shell Have Been Much Use?No!Most of the criticism I have read about refers to the British Army’s experience in N Africa, when Matilda, Valentine and Crusader tanks find themselves outranged by Wehrmacht anti-tank guns. When the M3 Lee/Grant tanks arrive from the US, their HE capacity (as well as high reliability) endeared them to the British tank crews.The tanks would have been up against 5 cm Pak 38 which were small and easy to conceal and 8.8 cm Flak 36 used in the A/T role- these were mainly used at long ranges and were accurate but hard to conceal.The performance of HE fire against anti-tank guns can be overestimated, however.With respect to indirect artillery fire against dug-in antitank guns we have some operational research data [Ref 11].Counter battery fire was carried out against German guns firing against Commonwealth units during Operation Veritable in 1945.3600 rounds of 80 lb 5.5″ fire landing in a 300 yard diameter area managed to knock out just 1 gun of a 5 gun battery. A second six-gun 8.8 cm battery was engaged with 5700 rounds landing in a 300 yard diameter circle. This savaging knocked out two guns! A bit better than the “Mad Minute” scene in Predator, but not much!Ok, let’s look at the effectiveness of small HE roundsThe 2 pdr HE had a fill weight of 63 g. This is similar to a No. 36 Mills Grenade, slightly more than a modern 30 mm Bushmaster cannon HE round and quite a lot larger than an M406 40 mm low pressure rifle grenade- as used in Predator!The M406 has a quoted effective area of about 75 sq m =800 sq ft. [Ref 12]. This is against standing men, it would be rather less effective against the crouching crew of an anti-tank gun. It should be noted that the effect of HE rounds is considerably moderated by terrain features [ Ref 13].Evaluations of small HE rounds were made during World War II: Ref 14Table 1: Calculated Vulnerable Areas of Small HE ShellsFor comparison, a 2 inch mortar round produced a vulnerable area of 1200 sq ft. Ref 15 assessed the effect of 2″ mortars as “negligible” against artillery.This assessment implies 2 pdr HE round would have been of dubious value against anti-tank guns in the Western desert.Annex B: HE capacity of the 2 pdr HE round"Ammunition Information Manual No.9" which is an official publication going into great detail about ammunition for the "Ordnance QF 2-pr Gun" (including the Littlejohns) and this gives the following data on the Shell HE/T Mk 2:Length of complete round: 17.577 inWeight of complete round: 4 lb 2 ozLength of projectile: 4.96 inWeight of projectile: 2 lb 6 ozFilling & Weight: RDW/BWX or TNT 2 oz 4.5 dr. (=0.14 lb= 63 g)Shell HE HV/T Mk is designed to replace Shell HE HV/T Mk2. The principles of construction are similar to those of the Mk2 shell, but fitted with the fuze DA No. 255. The trajectory of this projectile is similar to the APCBC shot up to 1,600 yards.Annex C: Confusion with the APHE round- an example [Ref 16]ReferencesHogg I (1996) Tank Killing, Sidgwick & Jackson pp 138-139,Fletcher D British tanks of WW2 page 46Chamberlin and Ellis British and American Tanks of World War 2Gudgin P Armoured Firepowerhttp://www.tankmuseum.org/ixbin/indexpl ... _=Vehicles"2 Pounder HE Rounds, Little John Adapter, Ammo Effectiveness" TopicFletcher D British Tank of Word War 2 Osprey.2pdr, 6pdr and HE shells?Hogg I (1978) British and American Artillery of World War 2 Arms and Amourhttp://www.wwiiequipment.com/index.php?option=com_content&view=article&id=73:2-pounder-anti-tank-gun&catid=40:anti-tank&Itemid=58ORS2 (1945) report 29 Effect of Counter Battery Fire in Operation Veritable section c.Royal Military College of Science (1980) Handbook of Infantry WeaponsWO 291/138, Influence of ground cover on performance of HE projectilesWO 291/496, Anti-personnel effect of small HE shell.WO 291/538, A preliminary estimate of the destructiveness of various projectiles against Motor Transport and ArtilleryWO.169/952 A.F.V. G.H.Q. MEF War Diary 1941

I can suggest a range of possible explanations rather than a definitive answer.The premise* behind the question is that shells fired at high velocity must be strong enough to withstand the firing stresses, which exceed those for low velocity projectiles, all being equal. A common example given is the considerably larger payload in the M4 Sherman tank’s M48 75 mm shell as compared to the high velocity 76 mm and 17 pdr guns (these contained 0.68 kg, 0.396 kg and 0.49 kg of HE respectively -see my answer How much damage did the 75/76mm high explosive shell, fired from a WW2 Sherman tank against soft targets, inflict as 390 grams of an explosive filler of TNT doesn't sound like a lot?)It is common in artillery to produce a range of firing charges, from small to high. This is rare in tank shells.However it was carried out. In front of me I have a British gunnery trial on the QF 17 pdr carried out in1945 [1]Three types of cartridge are use containing1 lb 10 oz for high explosive7 lb 12 oz for APCBC6 lb 12 oz for APDSLet us explore the topic.These are my thoughts, I bet I have forgotten some things and not all readers will agree- well that is what comments are for!What are the advantages of low velocity projectiles? [2]Lower firing stressesHigher trajectory which can enable shooting over obstructionsHigher trajectory which is superior for engaging horizontal targets, trenches etc.Higher effect on ground targets owing to lower burying in the ground before the fuze activatesLower impact stresses which should decrease the blind (dud) rate.Lower barrel wearSmaller cartridge so lighter ammunition and higher capacityWhat are the disadvantages of low velocity projectiles?Greater ballistic mismatch with AP ammunition.Higher susceptibility to ranging errors- particularly important for vertical targets.Lower penetration- some HE rounds have useful AP penetration for dealing with tanks with thin armour.Shorter rangeLonger time of flight so larger uncertainties when engaging moving targetsWhat are the advantages of thin-walled shells?Higher capacity for HE- this gives more energy in the projectile which gives more small fragments-ideal for attacking personnel [3]Ability for squash head attack of armour.What are the disadvantages of thin walled-shells?Higher cost of high strength steel - the US 75 mm HE had a similar payload to the British 88 mm calibre 25 pdr owing to better steel.Lower penetrationThe smaller fragments tend to have less range and penetration so may be less effective against transport and artilleryLower range as the density is lowerGreater wind drift effect for the same reasonGreater vulnerability to cook off or penetration by splinters, albeit the cartridge is more commonly the initiation for an ammunition explosion.Ok, now armed with this information, we can consider the question.Reason 1- Reticule ClutterOne reason could be keeping a ballistic match between ammunition. This is the reticule for a Tiger. On the left you can see the range settings for the machine gun, scaled out to 1200 m. On the right there is a single scale for 8.8 cm ammunition, ranged out to 4000 m. The triangle and carets in the centre are the Strichs used as a kind of stadiametric rangefinder-albeit I found my brain could never use it properly under time pressure in a simulation- how much worse if I was really going to be decapitated by a 17 pdr if I didn’t get that shot on target!!!Quiz question- what is this reticule from? Source: Steven Zaloga.As you can see, the multiple ammunition types mean a cluttered reticle here. How bad would it now get with arrange of charges!So one reason for having a single high powered cartridge is that it keeps the reticle clear. I have seen this reasoning used for the British heavy tank FV215 firing only HESH! [4]Reason 2: AccuracyA tank gun differs from a field artillery piece in a number of ways:Being (normally) a direct fire weapon (i.e. the gun fires at a target the crew can see, since WWI , field artillery often engages a grid reference). This means that a high velocity and flat trajectory assists in engaging targets such as vehicles and strongpoints.Having a smaller ammunition supply in a tank interior. Artillery in WWII often ranged on target, then moved to fire for effect. Taking a lot of ranging shots would soon empty the tank ammunition supply- flat trajectory wins again!*Note on PremiseThe Panther high velocity 7.5 cm Sprgr.42 HE round contained 0.635 kg of HE which is not vastly different from the 0.68 kg HE in the 75 mm M48 in the Sherman.The 17 pdr also got a higher capacity HE round late in the war which increased the HE content from 0.49 kg to 0.58 kg. Combined with the lower power cartridge it have an muzzle velocity of about 1800 fps rather than 2980 fps with APCBC, it HE capability was not that compared to the 75 mm.ReferencesWO195/9625 (1945) Investigation into causes of reported inaccuracy in the QF 17 pdr gunsFarrar CL & Leeming DW (1983) Military Ballistics a Basic Manual BrasseysCourtney-Green P R (1991) Ammunition for the Land Battle BrasseysBeresford R S & Sturtridge M I ( 1955) Tank Effectiveness Heavy Gun Tank FV215 WO 291/1431