Wednesday 28 March 2018

Sd.Kfz.222 Under Fire

A while ago, I posted how German armour fared under fire in Soviet trials. Recently, I found information on a similar British test. This time it was a hatch from an Sd.Kfz.222 being fired upon, but the conclusions were largely the same: German armour is too brittle and has a tendency to flake and crack. The test plate broke into four large pieces under fire from the 15 mm Besa at a velocity matching a range of 1500 meters at an angle of 30 degrees. The quality of the armour was worse than British armour made to I.T.70 requirements.








39 comments:

  1. There is no information where the "door" came from. If it was from the engine compartement and the PC was damaged by fire, it will turn the material brittle.

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    1. ...and you think the Brit testers would not be aware of, and think to note, that?

      Light armoured cars like the 222 were the small change of mechanised warfare, and their very purpose of existence (ie. forward recon and hit-and-run raids) made them disproportionately likely to fall into enemy hands in varying states of disrepair; I sincerely doubt anyone interested in conducting some test firings would have had any particular difficulties finding an unburned wreck to nick bits off of.

      I'd also remind you that a similar tendency to develop dramatic and quite alarming cracks across the entire plate was also found later in eg. Panther glacis plates... IIRC it was also noted that the quality of metallurgy varied wildly between individual vehicles; no doubt the inevitable byproduct of the patchy access to raw materials the German war industry wrestled with throughout.

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  3. I have the complete british post ww2 report on german AFV armor manufcature. I also have the US report from the NavTech MisEU, and I have lots of sources from BA/MA Freiburg.
    I know that they started working on new, austempered steel during ww2 for thin, bulletproof plating such as employed in Sdkfz, which required a simpler heat treatment (as opposed to the complex hurling in and out of the furnaces required for standart RHA armor timed to the next second) -they pioneered it- and it was extremely sensitive to secondary heat exposure which turns it brittle. Moreso than normal steel plate (british assessed that everything below 200° would have no effect, but this is only true for british MQ armor, and the british during ww2 didn´t fully understood temper brittlement, believeing it was created during the heat).
    Without having satisfying information about the origin You can jump to wrong conclusions.

    You will always have a scatter between good plates and bad ones. German armor was relatively lean in alloys but compensated with more sophisticated thermo-mechanical heat treatment and electrosmelted charges of higher quality than those used in Britain. The british report doesn´t give an indication of inferior ballistic performance of the german material. Some of it was superior to british products (incl. thin plate). It states, however, that some of the armor should never have been allowed and blames the manufacturer cut some conrers against the specifications. British armor quality was of high standart by itselfe. The difference between them is that the british specified resitence vs overmatching attack while the germans optimized against cal/ attack.

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    1. Yes, as always, everyone is wrong except the great critical mass, who knows more than the scientists actually performing the tests. Shattering plates actually means they're good quality, don't you know.

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    2. I'm tolerably certain by that time Everyone & Dog, Inc. knew perfectly well armour plate from burned-out AFVs was only good for scrap.

      You're grasping at straws something fierce here pal. To a degree that can't be healthy for your nails and fingertips.

      Also would point out that for all you keep waxing lyrical about, quote, more sophisticated thermo-mechanical heat treatment and electrosmelted charges of higher quality, unquote, we still have well-documented cases of *tank frontal glacis plates* splitting right across in tests. That's a CRITICAL part of armour on a frontline combat vehicle, unlike an engine hatch of a light armoured car; either those measures weren't quite so good at compensating for the perpetual famine of alloying elements as you'd like to portray them as or the German war industry had very serious problems with quality controls and consistency, or both.

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    3. How many glacis were made and how many split glacis You have photo documentation of? And You are really prepared to jump to generalizations from the handful of documentated cases?
      I have seen very many and catastrophic glacis plate failures are hardly rendered a normal occurance.

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    4. Allow me to quote the August '44 Isigny test report (https://worldoftanks.com/en/news/chieftain/chieftains-hatch-us-guns-vs-german-armour-part-1/):

      "b. Wide variation was found in the quality of glacis plate on the three tanks. Tank No.2 (hereafter referred to as the "best plate") sustained 30 hits at ranges from 600 to 200 yards without cracking. Tanks Nos. 1 and 3 (hereafter referred to as "average plate") cracked after relatively few hits."

      That's two out of three tanks tested suffering structural failure of their main glacis under fire. Bloody well better not be indicative of the average already for the sake of the people crewing the tanks, but it certainly tells us the German industry was turning out - and the military accepting - some fairly alarming specimens.

      Not that having to settle for shoddy products for want of anything better was particularly unusual of or exceptional to them; at least three of the major combatant militaries (Soviet, German and Japanese) all had to cut an increasing number of corners just to keep enough reinforcements, supplies and replacements flowing to the frontline as the war ground on and losses added up. (The Soviets were at least in the position to partially change tack once the manpower reserves started running low; AFAIK their late-war tactics started increasingly converging on the Western "advance by fire" paradigm.)

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  4. "Shattering plates actually means they're good quality, don't you know"
    I never said this. I stated instead that without documentation of where and under what conditions the sampling material was recovered, You cannot view test results as representative. Without having a statistically sufficient sample size, the result isn´t significant, anyways. BASIC STATISTICS.
    You were the one who cited burned out samples in other cases...

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    1. This is a trend with you. Every time a German plate underperforms you claim it was burned. According to you, every plate from every tank recovered on any side of the front line is from a burned up tank. It's incredibly convenient.

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    2. I have access to prooving ground data, that´s why I ask questions. By 1965, the british would have recognized the quircks of austempered armor plate and would have tested it with charpy V-notch tests and metallographic section examination first to make sure that they have unaffected sampling material. I cannot see any of these in this report.

      Also, the british evaluation of german thin armor testifies that they solved the problems the british experienced with I.T.70 high hardness, homogenious plate welding, particularely with transverse crack propagation.

      Instead of preselecting a single test, Peter, why not posting all results? The reader can decide for themselves whether or not the german material was inferior to I.T.70...

      https://imgur.com/a/8F3PY

      As you can see, in other cases, the "inferior" thin german armor had superior limits of velocity to I.T.70 grade HHA.

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    3. I have access to proving grounds data too, which is what I'm posting. What this proving grounds data doesn't have, however, is British armour falling apart into pieces under fire.

      Cool test. I see that you have figured out how to post images now, very impressive. I don't know why you're trying to prove by countering my test where German armour cracks and shatters with your test where German armour cracks and shatters.

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  5. As You might notice, the average of 12 plates tested by the british after the end of ww2 was judged by themselves 38fps above the specification quality for I.T.70 plate, with individual plates beeing as far as 104fps below and 122fps above specifications, respectively.
    This is a competetive performance considering that
    A)
    the german material had a chemically far leaner alloy composition
    B)
    the german material did not experience the sort of troubles with transverse crack propagation under welding which hit british I.T.70.

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    1. Actual British engineer: "The material is therefore considered to be inferior to our I.T.70 plate."

      A guy from the internet: "Actually everyone else is wrong and I am the only one who is right"

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  6. Peter, I just demonstrated again that Your selective citing practice leads to misleading conclusions from quoting a single, preelected test which fits whatever Your obvious agenda is here when a wide array of primary source material exist to show the wide picture instead.

    You don´t comprehend armor metallurgy, Peter. That always have been the problem with You and this blog. You switch from different penetration mechanisms to different conditions, You don´t recognize a projectile remains, nor what the failure modes mean.
    You seem to define armor quality only in crack or spall resistence and are so happy to judge it by A SINGLE TEST! Such a scientific practice! An elementary scholar can do better. I actually provided You a source with twelve plate test results by the same service of the same thin protective plating used in APC and the results are: In terms of reistence to ballistic attack they are Up to british I.T.70 specification quality (average of twelve plates was + 38fps). Yes, the austempered armor tended to spall more when hit by overmatching projectiles but it was free of welding troubles typically encountered in british I.T.70 applications and free of some critical alloys. Scientiest would call that achievement GOOD METTALLURGY.
    The germans specified armor according to ballistic resistence first against intact projectiles (because, unlike the, uhhhm, soviets, the germans actually possessed a decent quality service AP bullet which could penetrate without suffering break up and burst high order afterwards) and to spall resistence against cal. sized projectiles. The 15mm is already badly overmatching a 9mm plate so spalling has to be reckoned with under multiple hits.
    Sensible designers understood that it´s a balance between spall resistence and ballistic resistence. German armor is more optimized to the latter, US armor more to the former with british MQ beeing in between both but closer to german.
    Very soft armor, such as was specified by the US would not have been tolerated for plating where ballistic protection is required (witness M47 glacis failing to prevent PAK43 penetration). In german tanks, such armor grade was used, and even specified for mine protective plating where resistence to shock was paramount to ballistic protection.

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    1. Yes, my selective citing of posting a direct quote from the British scientist analyzing the plate. That's the difference between you and me. I don't pretend to have divined the true nature of the universe. My analysis relies on what is written in the report. It is the opinion of the British scientists that the German armour is inferior to theirs. However, your opinion about German superiority is just that: opinion. The people with the plates in their possession that went out and did the tests come to a completely opposite conclusion than to yours. Not just in this case, every time. And yet for some reason you disagree, despite having none of the resources that they did.

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  7. You preselect reports which fit Your agenda while deciding deliberately to hide any information You encounter which doesn´t fit Your agenda. I have no opinion about german superiority. I have a strong opinion against selective perception when I come across it. Particularely when people who don´t understand what they write about try to sell their "findings" as truth.
    You didn´t knew anything about austempered steel. You didn´t knew even under what conitions the sample was tested, yet You are too easy to jump to conclusions based upon an invalid sample.

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    1. I'm not making the conclusions. The British are making the conclusions. These are their words verbatim, no matter how much you want to frame their conclusions as my opinion, it's not my words that state that German armour is inferior. You say "I have access to prooving ground data", so post it.

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    2. cm mah boi, when your argument devolves into undiluted Ad Hominem like that it's time to step back and take a long hard look at what you're doing.

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  8. The british didn´t state german armor was inferior. A single test means nothing. After assesing all available tests to them, they were still uncertain. Some of the tested material was worse, some of it was similar, and some of it was better.
    The only thing they believed the germans made a mistake in armor was in tempering it to create high levels of charpy impact toughness and crack resistence. They even went so far to cut a 50mm BRUMMBÄR side plate in two and reheat-treated one side to proove their point. In subsequent trials, the impact toughness of the reheated plate was indeed improved, but the firing trials showed that the original plate had a higher ballistic limit, leaving them speechless.

    Do You mind to explain why You banned me from posting in the Heavy thread just when I posted prooving ground data?

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    1. >The british didn´t state german armor was inferior.

      Direct quote from the document: "The material is therefore considered to be inferior to our I.T.70 plate."

      Post those tests then. You keep going on about how you have these endless troves of information, and yet somehow we never see any of it.

      I must have told you a dozen times by now: I didn't ban you from anything. I can't ban anyone from anything. There is simply no provision in Blogger to do so. If you don't believe me then make a new account and post from there. Or make your own blog and check the settings. I don't understand your conspiracy theory about how Google's spam filter has a personal vendetta against you.

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  9. You used a direct quote from ONE document dealing with ONE trial, hardly representative. It´s a rather particular case, selected to fit Your agenda.

    Direct quote from post war 1946 british document (SUPP22/58) which deals with all information on armor tests available in addition to intellegence gathered in occupied Germany on how they made armour:
    (yes, a primary source which is more authoritative than Your single test in making conclusions)

    "SECTION II.
    "It was concluded during the war from analysis and microscopical examination of captured armour that all, or nearly all of German armour was made from electric furnace steel.
    (...)
    At least 80 percent of their armour was made from electric furnace steel, and the remainder was high quality open hearth steel made by a process not used in this country (Duplex process). The German armour was, therefore, of more uniform quality than British steel, which, in so far as rolled armour was concerned, was made only to a small extent in electric furnaces, while the remainder was made in about equal proportions in acid and basic open hearth funraces using the ordinary process."

    -the british concluded post war that german armor was of more uniform quality than their own RHA.

    I can post excerpts of the reports. Yet, I will wait until You post my memo in the Heavy thread. It contained four images from US, russian and german ACTUAL test data (rather than calculated tabulations), even though You do not like the results.

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    1. Uniform quality does not mean good quality. Not only are you refusing to admit that the British analysis concluded that German armour was inferior, you are unable to come up with any evidence otherwise, despite claiming at great length to have all these documents that allegedly prove me wrong.

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    2. Also if you're looking at actual test data, here's some:

      http://tankarchives.blogspot.ca/2014/05/german-steel-vs-soviet-steel.html
      Conclusions: "the quality of the foreign armour is lower than domestic homogeneous armour."

      http://tankarchives.blogspot.ca/2014/02/pziii-armour.html
      Conclusions: "The trials show that the brittleness of the German armour is due to its unsatisfactory characteristics."

      http://tankarchives.blogspot.ca/2017/11/panther-armour-quality.html
      Conclusions: "Gun performance is appreciably better than forecast and it must be therefore be concluded that German plate is not up to the standard of our Homogeneous M.Q. tank armour."

      Over and over again, if is found that the quality of German armour is not up to Soviet or British standards. This is not "ONE document dealing with ONE trial" as you claim. This is a consistent pattern that reliably shows up across multiple trials of multiple vehicles over a large span of time.

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    3. The Americans get in on the game too. Trials of PzIII armour conclusions, WAL 710/435: "From the data obtained in this firing it is indicated that German armor of this type is inferior to American homogeneous armour of corresponding thickness". Trials of PzIV welded joints, WAL 710/608: "...welds with very poor resistance to ballistic shock or fatigue service". Both the PzIII and PzIV armour tests found that the content of alloying elements in the armour was incredibly high for its function, and yet the performance was worse than American steel anyway.

      Examination of Panther armour, WAL 710/750 : "Inferior toughness, as evidenced by brittle fractures and low impact resistance has been reported in several investigations of German armour that were 2" and greater in thickness"

      Another Panther report: WAL 710/715: "In several other investigations made by the British, it was found that the notched bar impact values of heavy German armor (2" and over) were considerably lower than that of comparable British armour".

      Your claim of "one report" falls flat on its face. All evidence points to the fact that, at the time, it was commonly accepted that German armour was inferior in quality to British, American, and Soviet armour. Again, this is not just my opinion, like you claim. The evidence is right there.

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  10. Inferior toughness and inferior notched impact tests (IZOD or CHARPY) is not directly correlated with inferior ballistic resistence. You don´t comprehend these things. The british were crazy about impact toughness tests -which are physical tests, not ballistic tests- and yet WAL authors didn´t understood them.

    Tests on the BRUMMBÄR plates showed that improvements made on impact toughness did result in reduced(!) ballistic limits.

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    1. Ah, right, so here's the "critical mass is smarter than everyone else" argument. WAL doesn't understand metallurgy, the British don't understand metallurgy, the Soviets don't understand metallurgy, only critical mass understands metallurgy. Words like "inferior toughness" and "poor resistance" area meaningless, only opinion of the great critical mass matters.

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    2. What poor reistence? SUPP22/58 doesn´t state inferior resistence. I have quoted the excerpt. The ballistic limit was -in average- above british specification for this thickness. There is really little to choose from. German armor was exhibiting a resistence within the range of british MQ armor. How could that be inferior?
      British report A.T. 252 (originally classified SECRET) doesn´t state "poor resistence" either for late ww2 AFV armour. Let me quote:
      "8. The armour generally behaved in a manner similar to British machinable.
      (...)
      Conclusions
      Unlike previous experiences with PANTHER tanks, the armour plates, with one exception (hull roof) did not show any marked tendency of brittleness, and their behaviour was not unlike British machinable quality plates.
      (tab)
      (...)
      In this respect, certain success has been attained in this tank, as no major cracking or flaking was noticable on the plates liable to direct attack"

      German tests of british armour from Churchills left at the Dieppe raid 1942 showed that british MQ was similar in ballistic resistence to their own armor, albeit from less clean but higher alloyed steel and more variable in quality.

      And yes, the WAL authors couldn´t explain 1946 why the re-heat treated german 50mm plate exhibited a lower instead of the expected superior ballistic limit compared to the original plate, which was believed to be so "inferior" owing to a higher liability to crack under >cal attack and a noticably lower impact strength as measured by Charpy tool.
      Charpy impact tests were still new in Britain (1932 adopted) and already old in Germany (1907 adopted), they knew exactly what they were doing.

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    3. https://i.imgur.com/76dKnxQ.png

      Your defense is literally "alalalala I'm not listening". The British, American, and Soviet reports repeatedly call German armour inferior to their own.

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    4. I'm sure whatever German inspectors passed those plates that outright shattered under 76 mm shell impacts in the aforementioned Anglo-American Isigny test also knew exactly what they were doing.

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  11. One plate shattered at Insigny, after many hits. And the crack originated from a free edge effect. German armor was above specification quality -in average- than british MQ. I have posted the report which actually includes WAY MORE WARTIME DATA and it was of higher consistency, again, I have provided full quote. Your reliance of single, preselected trial, while not beeing able to provide the circumstances is just pathetic. But as always, Peter Samsonov does not understand what he is writing about, so no surprise here.

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    1. I have provided you links and quotes from many studies. The fact that you repeatedly ignore this evidence and harp on about how it's just my opinion (it isn't) from just one study (there are many) is what's pathetic here.

      You quoted a part of one document which says nothing about quality of the armour. This excerpt does not support your claim at all, yet you keep referring back to it as though it is some kind of holy grail of wisdom. You keep saying that you have all this amazing data, but you don't actually share any of it with us.

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    2. Your insistence that German armour only cracks in this one test is also false. As usual, the British come to conclusions opposite of yours.

      https://i.imgur.com/d3NbYuE.png

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    3. One plate shattered at Isigny huh.
      "Tanks Nos. 1 and 3 (hereafter referred to as "average plate") cracked after relatively few hits."

      Cool reading comprehension bro.

      Also tank armour is not ballistic vest trauma plates; it's not supposed to fall apart doing its damn job and accordingly isn't even remotely as simple to replace... and crying about edge effect is meaningless when, as already mentioned, practically every single period tank design had its glacis plate integrity compromised by any number of cut-outs.
      Yet by some wizardry most folks' plates seem to have failed to dramatically fall to pieces like that despite suffering from the selfsame handicap...

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  12. When You want to assess plate quality, You better deal with the plate and not with free edge effects, that´s how professional prooving ground personal today and even in ww2 often does. Only unskilled personal and Peter Samsonov would quote skewed data in an attempt to prove that a given plate is poor. Free edge effect does reduce the apparent thickness of plate by up to 15%. That gives a lot of scatter in the data if it is mixed with fair hits.

    You can cite many cases of PANTHER glacis hit events which were resisted or defeated without cracking in ductile mode too:

    http://www.ww2incolor.com/german-armor/501.html

    http://i.imgur.com/grkVzbD.jpg

    http://img515.imageshack.us/img515/5729/116pzpantherkoautumn441.jpg

    https://4.bp.blogspot.com/-Ya72xPGSorc/WGZwh6Sm3pI/AAAAAAAAG4k/_EuCxkzS05cJZ8EZ2cgIQQVFTxHGeiRJwCLcB/s1600/Panther%2Bhits%2Bto%2Bglacis2%2B16.jpg

    http://media.moddb.com/cache/images/groups/1/3/2074/thumb_620x2000/Panther_vs_Sherman.png11.png


    what You don´t know are the proportions in relation to failures. And what You don´t know in absence of a mneaningful statistic analysis is how it does compare with other tanks.

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    1. Wait a minute, so in response to me posting actual detailed trials, you whine and complain that there is not enough details and not enough information. However, then you retort by posting random photographs with absolutely no information about the details trials performed at all! Do you understand your own hypocrisy?

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    2. Tests on captured equipement are done with whatever you have to work with, which in the case of Isigny was a random sample of 3 Panthers in suitable condition (the far more numerous ones in *unsuitable* state were used to establish a ballpark estimate of appropriate firing distance in preliminary firings).

      Two out of three failing rather dramatically certainly does not sound like the average given the general trouble the kitty gave in frontal engagements; that such "bad eggs" were found on the frontline AT ALL however speaks volumes of the degree to which the Germans were obliged to sacrifice quality control for the sake of output.
      A rather well-attested problem that had dogged them from the start and only got worse over time owing to brutal economic and industrial realities, so I honestly have a hard time seeing why you're even trying to dispute the point. Their planners, designers and engineers did what they could to compensate for and circumvent such issues but they were no miracle workers.

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  13. I posted a british post ww2 report which refutes Your single test and is twelve times as significant in sample size. On the same plate material. You decided to ignore it. and for the record, the previous memo is not directed to You but to someone else.

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    1. You posted an excerpt from one test that did not discuss quality at all. I posted half a dozen reports that discussed both specific samples and the quality of German armour overall. Why do you believe that your single excerpt is more significant than many tests?

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