"Characteristics of armour penetration of cannons and effectiveness of mines on enemy tanks
Based on experience of combat and trials
- Trials against an 88 mm SPG "Ferdinand" show the following results:
- Armour of the SPG: roof: 45 mm, rear: 80 mm, side: 80 mm, front: 200 mm, gun mantlet: 110 mm, front hull: 200 mm.
- Effectiveness of firing:
- Anti-tank rifles: firing at the side armour from 80-100 meters with the BS-41 bullet penetrates 50 mm of armour forming a 20-22 mm deep indentation. Firing at the tracks can break track pins and the track links. The rifle can penetrate observation periscopes and jam the gun ball mount.
- 45 mm gun mod. 1937: from 300 meters the shell can penetrate the first armour plate and break up against the opposite side, splitting into small pieces and damaging the gun mechanisms and its crew, destroying the engines. From 150 meters, three subcaliber shells made complete penetrations 22 mm in diameter. From 150 meters, the armour piercing shell makes a 22-30 mm deep and 50-60 mm wide indentation. Firing at the front armour from 100 meters, the subcaliber shell makes a 50-60 mm deep indentation. The core remains in the armour. The armour piercing shell makes a 25-30 mm indentation in the front armour.
- 76 mm mod. 1942 ZIS-3. The subcaliber shell makes a penetration 27 mm in diameter from 400 meters. The depth of the indentation is 100 mm. The destructive power is the same as of the 45 mm subcaliber shell. The armour piercing shell makes a 22-30 mm deep dent 400 mm in width. Firing at the front armour from 200 meters with a subcaliber shell makes a dent 100 mm deep and 110 mm wide, the core remains in the armour. The armour piercing shell makes a 35-37 mm deep, 110 mm wide dent. Firing at the tracks destroys the track pins and destroys the tracks. Firing at the gun mount jams it.
- 76 mm mod. 1927. The HEAT shell penetrates the side armour to a depth of 45-50 mm.
- 85 mm mod. 1939 AA gun. The armour piercing round can penetrate the side from 800-1200 meters. The breach is 110 mm wide from the outside, 200 mm from the inside. After penetrating the armour, the shell makes a 57 mm deep indentation in the other side, after which it bursts, showering the crew with its own splinters and armour fragments, destroying components.
Firing at the front armour from 200 meters results in a 100 mm deep dent, with spalling and destruction of the rivets holding on the applique armour, as well as destroying the controls and radio equipment. If a shell hits the track, it is destroyed within a radius of 0.75 meters. - 122 mm mod. 1931/37 gun. Firing an HE shell from 400-800 meters at the side armour with the fuse set to delayed action gives the following results: deep cracks are formed along the welding seams spanning the entire length of the casemate, the bolts of all the plates connecting the casemate at the bottom were torn off.
- 122 mm mod. 1938 howitzer: firing HE shells from 400 meters is ineffective.
- Effectiveness of anti-tank mines: in the prior defensive fighting, our units used chiefly YaM-5 mines, which are not entirely effective against PzVI tanks and Ferdinand SPGs. Practice shows that they are effective in destroying PzIII and PzIV tanks. Several areas had HE mines (50 kg charge connected to a 250 kg bomb) installed. The effectiveness of these mines is high. If a PzVI tank or a Ferdinand hits this mine, it is reduced to a heap of metal.
- Effectiveness of incendiary bottles: the most vulnerable area of the Ferdinand to bottles with incendiary fluid is the top armour where vents are located. It is easiest to disable the Ferdinand with bottles of incendiary fluid tossed onto the vents on top of the front part of the hull. It is also possible to throw a bottle into the hull through one of the hatches. The most convenient hatch for this is positioned in the rear of the casemate. This hatch is used to throw out spent casings during combat, so it is frequently open.
Chief of Staff of the Armoured and Motorized Forces of the Central Front, Colonel Korotkov
September 24th, 1943."
From what I conclude from this is "no matter how 'impenetrable' your armor is, it's always better not to get hit at all".
ReplyDeleteIs the 122 mm mod 1938 the same or equivalent to what was mounted on the SU-122? Vassily Krysov's memoirs claims that could disable a Ferdinand with a side it, at least.
If you hit the tracks, definitely, plus if you hit a welding seam or form a crack you would certainly do some damage. The M-30 was considered a fairly ineffective anti-tank weapon in general, except when armed with an AP shell from the A-19 (but that increased chamber pressure to unacceptable levels).
DeleteExactly, and a Ferdinand couldn't avoid any one thanks to it's weak motors. To make matters worse it lacked a turret or protective machine guns.Furthermore as soon as anyone (including infantry) got to it's side and knocked out a track it was defenseless. Germany would of been better off leaving off 20 tons of armor and adding a few machine guns. At least this way as soon as the battle starts going south, the engines would be strong enough to escape.
DeletePeter, I went to WarThunder (admittedly maybe not a great source) and it listed the anti-armor capability of the OF-462 HE round fired by the M-30 122 mm howitzer as being identical to the HE OF-471 fired by the A-19 gun. That's despite the weight of the OF-462 round being 22 kg versus 25 kg (A-19), so that might not be right.
DeleteIn Kysov's book, one of his regiment's SU-122's fires a round that hits the tracks of an oncoming Ferdinand, breaking it and causing the Ferdinand to swing around. At that instant, his SU-122 and that of another both shoot rounds into the Ferdinand's now-exposed side armor, both of which destroy the vehicle (and cause one of his crewmates to cry out "a wasted round!!").
Krysov also gives a speech before the action (Krysov was posted in the 1454th, attached to the 48th army, so his unit could have seen Ferdinands) reassuring his nervous colleagues their SU-122s can take out a Tiger at 500 meters or less.
Post war Soviet studies found that the velocity of an HE shell is a quite important contribution to the penetration, so World of Tanks (and I guess War Thunder) modelling it without considering distance is wrong.
DeleteI don't understand why are so many complains about the lack of machinegun in the Ferdinand, noone of the Soviet tank destroyers nor SPGs did have it and I have never read anyone missing them.
DeleteWere the Soviet combined infantry tactics superior to German? Maybe
Delete@ Motzkor. The slow Ferdinand was suppose to be protected from enemy infantry by German infantry. But, because the Ferdinands were targeted by heavy artillery to the extent they were German infantry could not stay close to them.
DeleteI understand what you say Mobius. But if that was true the SU122, ISU122 and the ISU152 would had face the same problem, the not as slow SU76, SU85 and the SU100 too. I have never read any complain about this in any of them.
DeleteTaking what I have said in account the problems the Ferdinand faced due to the lack of a machinegun are in my opinion a myth or an excuse.
Then one would have to find some battle where the Elefant's machinegun made a difference. Maybe some battle in Italy. Where allied soldiers were killed or suppressed by the machineguns. Other than that it is a red herring.
DeleteKing Tigers have been knocked out from the front because shell fragments have entered the tank through the machinegun mount.
Modern tanks do not have their armor compromised by a machinegun port so it is an obsolete concept.
Looking again at Krysov's memoirs; I mis-remembered them, conflating two separate events. The attack by the Ferdinand on his front was repulsed by breaking the vehicle's tracks, and was followed by something like five direct hits on the vehicle by 122 mm rounds. None of these hits apparently caused any externally-visible damage to the Ferdinand, but the crew, covering their ears, jumped out and abandoned the vehicle.
DeleteThe other event I recalled involved a tank attack, which included Tigers but also PzIIIs and PzIVs. One tank (it could be a Tiger, but it is not explicitly stated) was first hit with a shell on its track, causing it swerve, and two successive 122-mm hits, one on its exposed side, took it out. Another tank, described as a Tiger, took repeated hits but had its turret jammed by a 122-mm hit.
All this occurred in the fighting around Ponyri station, where there were definitely both Tigers and Ferdinands engaged.
The machinegun port was an obsolete feature of the German tank Mobius, but it was not the only one. The motor/transmission layout was the biggest obsolete feature of German armored vehicle design. It made the vehicles bigger, heavier, less armored more complicate and expensive to produce/mantain and the stability advantage it gave not so big in the real world.
DeleteThe solution was in front of them since the beginning of the war. But those who believed themselves superior to any other human were not capable to implement it in their production vehicles.
In all fairness the Germans themselves seemed to feel adding the bow MG to the Elefant/Ferdinand was worth it, if now only for the crew's peace of mind. And ofc the US retained bow MGs in tanks until the M48 of early Cold War era so hanging onto such old ideas of questionable utility was hardly something unique to the Germans.
DeleteThe latter likewise retained the "cross-hull" arrangement of engine and final drive essentially throughout the war (the handful of Pershings that made it to the front before the end can hardly be counted) and duly had the same issues of added height and volume plus corollaries in their tanks, it was a fairly common design paradigm at the time. The German and US engineers just stuck to it longer than most for whatever reasons.
Maybe they miss the machinegun because they were used to it, but lacking the hull machinegun was not such a big problem as Soviets demonstrated.
DeleteThe Germans were very good designing some pieces of the equipment of the vehicle such as the weapon systems. But if we take the vehicles as a whole Soviets were the most advanced tank designers of the WWII. The points we are talking about here are a clear example of it.
Most versions of the Brummbar had no protective machinegun. No one has lamented that.
DeleteThat backs my point, "the problems the Ferdinand faced due to the lack of a machinegun are in my opinion a myth or an excuse."
DeleteThe Soviets added the option of a flexible AA MG mount to their bigger and later SPGs though (one imagines SU-76 crews were expected to use their standard-issue SMGs over the sides if necessary), and the Germans tended to be pretty consistent about having MGs on theirs - the "Brummbär" got one too in the fourth and final production version so apparently somebody DID take issue with the initial lack thereof.
DeleteThe Americans were also keen on having at least one MG for AA duty and infantry suppression in theirs so clearly there was a general feeling that such secondary antipersonnel weapons were desirable. If nothing else they allowed engaging soft targets without having to expend the more limited reserves of main-gun ammunition, and likely also served as an useful psychological prop for crews - AFVs are more willing to risk being subjected to infantry assaults if they're equipped to fight such off, much like hand-to-hand training makes infantry more willing to risk or enter close combat (and having some form of antitank weapon makes them that much more willing to hold against armoured attacks).
There was also the fact that the bow MG was the only (somewhat) stabilized weapon a tank had on the move (discounting tanks with stabilized or free-elevation main guns), so it was an asset that way. At the same time tanks typically had the spare crewmember (albeit not on all tanks the crewmember had another duty such as the radio), and mountings were typically in such a way that they didnt compromise protection either.
DeleteThen again, the russians were pretty much the only ones who considered a fixed driver-operated machinegun useful (for making noise I suppose since you cant aim without making the main gunners job harder), as the IS-1 had it and various tanks (T-70, T-44/54 (not sure which or both) had it at least proposed in some form. (Im aware of the US tendencies on the M2/M3 Mediums, but they hopped off that train rather than on it)
Some interwar French and private-sector US (eg. Marmon-Herrington) tanks also had fixed driver-fired MGs. Always assumed the idea was simply throwing more suppressive fire in the direction of the advance as I can't recall ever seeing descriptions of the actual contemporaneous reasoning behind such weapons.
DeleteThe T-44 had a fixed internal MG in the middle of the glacis, of all places, and the very first T-54 production series had external fixed MGs carried on the fender but those were dropped from later runs, presumably as superfluous and waste of good guns. Though if you count prototypes that never made it into production the IS-7 is a hard act to follow in terms of more dakka - I'm counting something like 7 MGs including at least one KPV in the description (http://tankarchives.blogspot.com/2016/05/is-7-titan-late-for-war.html)... the fixed backwards-firing ones in the rear corners of the turret certainly were a pretty unique (if not necessarily terribly practical) idea.
And, of course, then you had the US M2 and early M3 Lights which were something of an experiment in "how many MGs can you cram into a small tank before the crew drowns in them?" Turned out the internal fixed sponson ones were a bit too much (also rather silly and not very useful) so they were junked already in the M3A1 ("Stuart III" in Britisher taxonomy).
DeleteThe IS-II had a metal sleeve on the front right side of the hull for firing a MG through. It can't determined it one was actually provided.
Delete"Is the 122 mm mod 1938 the same or equivalent to what was mounted on the SU-122? Vassily Krysov's memoirs claims that could disable a Ferdinand with a side it, at least."
ReplyDeleteDon't forget the Russians were mis-identifying STUGs as Ferdinands as late as November 1943.
In Objective Ponyrii, by Martin Nevshemal there is note of Ferdinands being knocked out from the side by SU-152s.
"Ferdinand" became the catchall term for German casemate SPGs though.
DeleteAnd the 152 mm packed enough punch to knock out about anything from any direction so, well...
Krysov's memoirs are not without flaws (he wrote them at age 90) and he has Panthers erroneously facing the 48th Army (even though he does not mention seeing or fighting any) directly.
DeleteBut looking at where there were Ferdinands, placing them in 48th Army's front is not unreasonable, and the fact there are a plethora of photos of knocked-out Ferdinands from Kursk showing that these weren't due to mistaken identity.
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ReplyDeleteThe Article mentions 'Subcaliber rounds' for both the 45 mm gun mod. 1937 and the 76 mm mod. 1942 ZIS-3; would these be APDS rounds such as the British used?
ReplyDeleteAPCR, as far as I know the USSR didn't develop APDS ammunition.
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