T-44 vesrus Panther

[Timber]

It can't be Vo at 2000m, just V

What is the source?

Yes thats right, but noone is perfect just a simple "Typo"

The source is simple "math" buddy However i recieved this info from a friend, who's got a book about kinetic energy and projectiles, so i didnt calculate it myself, but i took alot of notes. (Ill try and get the title for you)

Regards.

[Ace31]

The Panther turret was located in center beacuse it used a FWD what was big mistake!

Excuse me, I don't understand your assertion...
It was a mistake:
- central turret together FWD ? (Why ?)
- FWD ? (yes, there're a lot of disadvantages, but also some advantages)
In the second case, in general I agree with you, RWD was better solution, but consider FWD a "mistake" seems to me too much strict.
But, about first case, I really don't understand what you want to say...

[Huck]

No, they do not have a scientifically proven theory.

We have to observe that all that Livingston & Bird theory produces are empiric formulas. In order to prove an empiric formula, the researcher has to observe the fenomenon he is trying to model with his empiric formula, measure the results and compare them with the results produces by his empiric formula. To my knowledge Livingston & Bird never fired a shot. This means it is an unproven theory, like another milion of them.

You miss the fact that their formulae are based on actual WWII firing tests and primary source material relating to those tests. Also, they build on scientific reports made in the immidiate postwar period which are also based on empirical evidence.

I don't loose the sight of anything. I'm perfectly aware that they had as input data actual firing tests. Problems arise when they try to settle with their calculations disagreements between the actual fire tests themselves, calculations of which veracity cannot be assesed until another set of firing tests are done to validate them. This basic requirement of any empiric formula has to be satisfied if we are interested in a scientific manner of validating the results.

For example, they tried to give an explanation of how IS-2 122mm gun could penetrate Panther's glacis at 2500m, as Soviets maintain it happened. Well, this test is a very controversial one. According to WaPruef 1 from Oct 5 1944, the 122mm could not penetrate Panther's glacis, not even at point blank.

These WaPrüf tables are notoriously unreliable and does not appear to have anything to do with actual vehicle vs vehicle tests. They may be based on actual measurements on captured vehicles and possible on a testfiring of the guns, but the vehicle vs vehicle data is deeply flawed and most likely calculated on the basis of whatever was known about armour penetration theory in Germany at the time.

Gun vs vehicle tests will always generate less consistent results that gun vs armor plate tests (even if we do not consider the variations between armor plates BHN). The assembly of the armor plates drastically modifies the protection offered by the plates themselves. For example an increased number of angles in the hull can theoretically give better protection (like IS-3 front), in practice the protection is worse because the increased number of weldings decreases the hardness. Another important reason is that captured vehicles were most of the time damaged, worn-out or of substandard quality that crews were happy to abandon. Tests on such vehicles are unlikely to give an accurate picture of the actual capabilities offered by the factory fresh vehicles. Considering all this, it is obvious why gun vs (captured) vehicle tests are so inconsistent. In this regard WaPrüf tests are not better or worse than any similar Allied tests.

This is in fact suggesting that the Germans overestimated the effects of slope because they did not now about the importance and function of the T/D ratio.

Of course they used T/D ratio in their estimations, where did you get this idea from?

The Brits also found that 17 pdr, a gun slightly more powerful than both KwK 42 and D-25 (the Brits usually used better quality ammo in tests, its effectiveness was lower as supplied to combat troops), succeded to penetrate Panther's glacis only from 50m in 50% of the hits.

Source?

WO 291/171, "Effectiveness of British anti-tank guns", wartime report.

Here it is worth noting that the 100mm gun got consistently worse ratings than the 122mm gun in Russian tests simply because it could not be produce in sufficient numbers. Later, in postwar years, when the 100mm gun went into large scale production the ratings reversed.

Source?

Sources abound on this matter. Only in Autumn 1944, when mass production was insured of the 100mm gun was secured, all tests gave the 100mm as a clear winner. First are the trials made in December IIRC in order to decide the weapon for the largest SU SPAT on T-34 chassis. 100mm gun won the trials without problems.

The documents available on the Russian Battlefield site from August 1944 seems to suggest the exact opposite. In response to Berias request, it is said the the 100mm is clearly the better weapon but that the 122mm should be retained, because the changeover would jeopardize tank production and because the superior HE performance of the 122mm was necessary.

That's because you haven't read them in chronological order. This is their first reply on Beria's request.

"Top Secret

To Comrade L.P.BERIA

According to your order about mounting the 100mm D-10T gun onto "JS" tanks, I have to say the following:

1. At the moment, "JS" tanks armed with the 122 mm main gun are successfully repelling all counterattacks by German tanks of all types at all ranges (i.e. up to 1500 metres);

2. Rearming some tanks with the 100mm gun will cause considerable confusion and problems with ammo supply;

3. Rearming some tanks with 100mm gun will lead to decreasing the firepower of a tank during combat with enemy infantry and pillboxes, because 100mm explosive power is significantly less to the 122mm round;

4. The "JS" tank is limited to 28 122mm rounds or 29 100mm rounds, therefore its ammo load will have to small an increase to take it seriously;

5. There are well known troubles with loading such long 100mm rounds. Moreover, intensive fire from 100mm guns would lead to increased fumes in the fighting compartments of the tank, therefore the real rate of fire of the 100mm gun would be decreased anyway.

Taking into account all the comments above, I think that rearming "JS" tanks with the new 100 mm D-10T gun is not expedient.


Fedorenko

6.VIII.1944"

Which is very understandable, considering the menacing way Beria formulated his request (I suggest you read about Comrade Stalin and Comrade Beria presence in armor development meetings, you don't seem to take it seriously).Later, when they certain that there were advanced plans to put the 100mm in mass production by the end of the Autumn, their tune changed.However another test from Sept 1944 comes again with the old bias, "122mm is the only available for the Soviet tank crews so it certainly outperforms the 100mm":

"Top Secret

September 12, 1944

To the chairman of the technical Council of the People's Commissariat for Armaments of the USSR, Comrade E.Satel.

REPORT

According to the results of the test shooting performed against the German Panther tanks at the Kubinka Proving Grounds of the GBTU the guns tested in order of decreasing effectiveness against the frontal armor of the Panther are as follows:

1. The D-25 122 mm tank gun manufactured at the factory #9. Its ballistic characteristics are identical to those of the following guns: the A-19 122 mm, the D-2 122 mm (factory #9) and the S-4 (Central Artillery Design Bureau), giving it a muzzle velocity of 780-790 m/s with a 25 kg projectile. This gun reliably penetrates the Panther's frontal armor at 2500 metres, and that is less than its maximum range.

2. The D-10 100 mm tank gun with ballistics identical to those of the BS-3 100 mm gun, its muzzle velocity being 890-900 m/s with a 15.6 kg projectile. This gun can penetrate the frontal armor of the Panther at up to 1500 metres, which is its maximum range."

Clearly, the different agencies does not quite agree, but there is no reason to go look for conspiracies.

What conspiracy are you talking about? Those engineers tried to save themselves and their families, I find their attitude very much excusable.

And in any case, if you look at Bird & Livingstons formulae and penetration figures, they clearly show the 100mm to be superior and that the 100mm would penetrate the Panther glacis at longer ranges than the 122mm.

I wonder how ridiculous they can get. So they think the 100mm could penetrate Panther's glacis at 3000m, 3500m? what was the number?

The only problem here is the somewhat dubious Panther flawed glacis (which was never, to my knowledge,

made of cast steel - it was always rolled armour plate) theory.

My mistake, I was writing fast. I mixed it with cast turret front. Indeed Panther's glacis is made of RHA.

But take note that this theory is forwarded only as an attempt to explain the strange Soviet claim of a 2500 meter penetration which DOES NOT correspond with the Bird & Livingston formula. They are not argueing that the 122mm could penetrate a normal, good quality Panther glacis at 2500 meters. They are saying, that if it happened, then there must be some kind of problem involved. Hence the flawed glacis theory.

There was no need for a justification for this Russian claim, simply because it is an absurd one. However I cannot stop myself from noting that their theory is so lax that it can adapt to the most outrageous claim. Then what's the use for it, if you can prove whatever nonsense with it?

Considering the number of Panthers and other German tanks pictured with cracked armour, it is not an unlikely theory, but were Bird & Livingston have been criticized is in their estimation on how many

Panthers had flawed plate - they suggest about 50% which seems rather dubious.

Considering the large number of destroyed German tanks floating around I don't see the procentage of Panthers found with cracks unnatural. There are plenty of photos of Russian tanks with cracks in armor. The thicker or harder the armor is, the more likely are the cracks in armor when hit by powerful rounds.

[cbo]

I don't loose the sight of anything. I'm perfectly aware that they had as input data actual firing tests. Problems arise when they try to settle with their calculations disagreements between the actual fire tests themselves, calculations of which veracity cannot be assesed until another set of firing tests are done to validate them. This basic requirement of any empiric formula has to be satisfied if we are interested in a scientific manner of validating the results.

So what you are saying is that you cannot say anything about armour penetration of WWII projectiles on WWII tanks without firing WWII guns and projectiles vs WWII tanks. That is a rather silly position in my view

Gun vs vehicle tests will always generate less consistent results that gun vs armor plate tests (even if we do not consider the variations between armor plates BHN). The assembly of the armor plates drastically modifies the protection offered by the plates themselves. For example an increased number of angles in the hull can theoretically give better protection (like IS-3 front), in practice the protection is worse because the increased number of weldings decreases the hardness. Another important reason is that captured vehicles were most of the time damaged, worn-out or of substandard quality that crews were happy to abandon. Tests on such vehicles are unlikely to give an accurate picture of the actual capabilities offered by the factory fresh vehicles. Considering all this, it is obvious why gun vs (captured) vehicle tests are so inconsistent. In this regard WaPrüf tests are not better or worse than any similar Allied tests.

So you assume that the WaPrüf charts represent actual gun vs vehicle tests?

If the WaPrüf figure are correct, they must have found some extraordinarily well made Shermans for their tests.......

You may believe these WaPrüf charts, that is your privilege, but I think they are just as outrageous as the 2500m penetration of the Panther glacis by the 122mm.

Of course they used T/D ratio in their estimations, where did you get this idea from?

It would explain why the WaPrüf data consistently overestimate the protective qualities of sloped armour. If they did use T/D ratio in those calculations, it is hard to understand how they could get it so horribly, consistently wrong. Do you have any references suggesting that the Germans did use T/D ratios in their calculations?

Sources abound on this matter. Only in Autumn 1944, when mass production was insured of the 100mm gun was secured, all tests gave the 100mm as a clear winner. First are the trials made in December IIRC in order to decide the weapon for the largest SU SPAT on T-34 chassis. 100mm gun won the trials without problems. <SNIP>

Sorry Huck, I dont see any engineers desparetely trying to hide from anything. Again, looking at the documents on the Russian Battlefield, what I see is three simultaneous responses to a request from Beria. Beria writes to

Malyshev
Ustinov
Fedorenko
Yakovlev
Kirpichnikov
Borisov
Petrosiants
Vannikov

on August 3rd 1944, requesting their views on the matter of the 100mm vs the 122mm.

Fedorenko writes Beria on August 6th that he thinks the 122mm should remain, Malyshev responds August 8th and thinks the 100mm is superior while Ustinovs people write him on the same day, stating that they think the 122mm should remain.

Evidently, there are different positions on this in August 1944.

(For those who dont know, the documents are here:
http://www.battlefield.ru/library/archi ... s4_01.html
http://www.battlefield.ru/library/archi ... s4_02.html
http://www.battlefield.ru/library/archi ... s4_03.html )

The September 12th letter you quoted seems completely unrelated to Berias request in August?
(and this is: http://www.battlefield.ru/library/archi ... pons5.html )

I'm not sure how good the translation of the document is, but I get the impression that they are saying that the max. range of the 100mm gun is 1500 meters, and at this range it penetrates. I dont think it is entirely clear whether it could in fact penetrate at longer ranges if the range of the gun was longer.
With regards to the 122mm, they say it penetrates at 2500m which is inside the maximum range of the gun and as such it is considered a valid result. But the report does not say that these results are conclusive, far from it. It is clearly stated that the results were preliminary and there are lot of ifs and buts about the results. I just dont see any engineers shaking in their pants, just aiming to please Stalin or Beria.

I wonder how ridiculous they can get. So they think the 100mm could penetrate Panther's glacis at 3000m, 3500m? what was the number?

You dont know? I would assume that you had to know Bird & Livingstones work to criticize it - particularily given your rigid view on "science" referred to at the beginning of this post......

There was no need for a justification for this Russian claim, simply because it is an absurd one. However I cannot stop myself from noting that their theory is so lax that it can adapt to the most outrageous claim. Then what's the use for it, if you can prove whatever nonsense with it?

That is where your lack of understanding of Bird & Livingstones work shows. The whole issue is that the 2500m penetration of the Panther glacis by 122mm APBC did NOT fit their formulae.

You need to understand, that they do not correct their formulas for standard penetration by APBC vs 240 BHN RHA to fit this Soviet report. Their standard formulas results in penetration at a considerably shorter range.

So they choose to explore the problem and find out why. That is were they came up with the flawed glacis theory which is an additional formulae that you can apply IF you think it is appropriate. Just like their additional formulae for cast armour, hard armour, face hardened armour etc.

Where they fail, in my view, is that they assume that 50% of Panthers had this "flawed armour". I just dont see any evidence of that.

So my take on the infamous 2500mm Panther glacis penetration by 122mm APBC is that it may have happened vs a Panther with flawed armour, an old burnt out wreck, a tank already shot up or whatever, but it is not something that can be properly verified nor should one assume that it was something that would happen on a regular basis on the battlefield. Or it could be some kind of bureaucratic screw up, like those in the US Army who were convinced that the 76mm M1 gun could penetrate the Panther without problems and told that to Eisenhower

But it does not mean that the basic formulas Bird & Livingstone have published are rubbish, it means that a very small addendum to those formulas is dubious. And if you dont think the "Panther flawed armour" theory is any good, then just dont apply it when you use the formulas (I dont).

Claus B

[Ultramagnus]

Another important reason is that captured vehicles were most of the time damaged, worn-out or of substandard quality that crews were happy to abandon.

Damn it,that is a good one

Time damaged armor steel? What comes.

Worn out? Mechanically maybe?

Substandard quality? Yes,the crews were abandoned their valuable,big and expensive tanks because they had found the armor quality suspicious. It's great to learn a new thing everyday

[WotS]

The Panther turret was located in center beacuse it used a FWD what was big mistake!

Excuse me, I don't understand your assertion...
It was a mistake:
- central turret together FWD ? (Why ?)
- FWD ? (yes, there're a lot of disadvantages, but also some advantages)
In the second case, in general I agree with you, RWD was better solution, but consider FWD a "mistake" seems to me too much strict.
But, about first case, I really don't understand what you want to say...

Sorry but the english is not my native language.

If tank tank has FWD then the transmission is in front and there is just no room for turret so it is located in center.

[Ace31]

Sorry but the english is not my native language

I too

If tank tank has FWD then the transmission is in front and there is just no room for turret so it is located in center

Oh, yes, this is right !
But this components positioning make weight distribution more homogenous and increase frontal protection due the presence of final trasmission/steering sistem in the front...

[WotS]

Sorry but the english is not my native language

I too

If tank tank has FWD then the transmission is in front and there is just no room for turret so it is located in center

Oh, yes, this is right !
But this components positioning make weight distribution more homogenous and increase frontal protection due the presence of final trasmission/steering sistem in the front...

No!It is not true.
When the tranny is in rear then the nose angle is sharper!This means more protection.

[Huck]

I don't loose the sight of anything. I'm perfectly aware that they had as input data actual firing tests. Problems arise when they try to settle with their calculations disagreements between the actual fire tests themselves, calculations of which veracity cannot be assesed until another set of firing tests are done to validate them. This basic requirement of any empiric formula has to be satisfied if we are interested in a scientific manner of validating the results.

So what you are saying is that you cannot say anything about armour penetration of WWII projectiles on WWII tanks without firing WWII guns and projectiles vs WWII tanks. That is a rather silly position in my view

Please, don't put words in my mouth. By now, it should be clear to everyone what I have said. Penetration is far from being a deterministic process, we have probabilities associated with each penetration value. If the penetration values comming from different sources for a particular gun, ammo, armor plate hardness, distance and obliquity are in the vicinity of the mean value of the normal distribution that fits the original distribution of penetration values then we can consider those values as valid. If those penetration values are in a stark disagreement, being far from the mean value, we have to discard them as outliers. This is the case with the 122mm vs Panther glacis in German and Russian tests, both have to be rejected.

Another thing. When sources are in stark disagreement on penetration values, de Marre and alike formulas cannot help us decide which source is correct. De Marre and alike formulas work wery well at small obliquities and soft steel armor that is unable to deform or shatter the projectile. That De Marre formulas could not give estimations with reasonable accuracy of the penetration of sloped face hardened armor was perfectly known during ww2. De Marre formulas remained in use until late 60's, simply because there was nothing to replace them with. From then on superior mathematical modelling tools were developed, helped by the wide spread of mainframe computers in research facilities.

Gun vs vehicle tests will always generate less consistent results that gun vs armor plate tests (even if we do not consider the variations between armor plates BHN). The assembly of the armor plates drastically modifies the protection offered by the plates themselves. For example an increased number of angles in the hull can theoretically give better protection (like IS-3 front), in practice the protection is worse because the increased number of weldings decreases the hardness. Another important reason is that captured vehicles were most of the time damaged, worn-out or of substandard quality that crews were happy to abandon. Tests on such vehicles are unlikely to give an accurate picture of the actual capabilities offered by the factory fresh vehicles. Considering all this, it is obvious why gun vs (captured) vehicle tests are so inconsistent. In this regard WaPrüf tests are not better or worse than any similar Allied tests.

So you assume that the WaPrüf charts represent actual gun vs vehicle tests?

If the WaPrüf figure are correct, they must have found some extraordinarily well made Shermans for their tests.......

You may believe these WaPrüf charts, that is your privilege, but I think they are just as outrageous as the 2500m penetration of the Panther glacis by the 122mm.

Please quote me correctly. On 18 Jan 2005 03:14 I said in the very same thread:

"Now, why Livingston & Bird chose to believe the Russian test and not the German or British ones its hard for me to understand. If the sources are in such a terible disagreement the most sensible thing to do is to disregard both."

Of course they used T/D ratio in their estimations, where did you get this idea from?

It would explain why the WaPrüf data consistently overestimate the protective qualities of sloped armour. If they did use T/D ratio in those calculations, it is hard to understand how they could get it so horribly, consistently wrong. Do you have any references suggesting that the Germans did use T/D ratios in their calculations?

Of course. In the '30s Krupp maintened an so called Atlas of Penetration that gave approximation for penetration values for all German and foreign naval guns/shells (from smallest to largest calibers) against the known types of armor. Actual firing tests were used as starting point, for calculating parameters needed in order to estimate the penetration at different distances and obliquities. Here's one of the formulas used by Krupp:

T/D = (0.30386) * D^0.25 *[(W/D^3) * (V/C)^2]^0.625

Note the use of T/D ratio. In fact Krupp used T/D in formulas prior De Marre.

Sources abound on this matter. Only in Autumn 1944, when mass production was insured of the 100mm gun was secured, all tests gave the 100mm as a clear winner. First are the trials made in December IIRC in order to decide the weapon for the largest SU SPAT on T-34 chassis. 100mm gun won the trials without problems.

Sorry Huck, I dont see any engineers desparetely trying to hide from anything. Again, looking at the documents on the Russian Battlefield, what I see is three simultaneous responses to a request from Beria. Beria writes to

Malyshev
Ustinov
Fedorenko
Yakovlev
Kirpichnikov
Borisov
Petrosiants
Vannikov

on August 3rd 1944, requesting their views on the matter of the 100mm vs the 122mm.

Fedorenko writes Beria on August 6th that he thinks the 122mm should remain, Malyshev responds August 8th and thinks the 100mm is superior while Ustinovs people write him on the same day, stating that they think the 122mm should remain.

Evidently, there are different positions on this in August 1944.

(For those who dont know, the documents are here:
http://www.battlefield.ru/library/archi ... s4_01.html
http://www.battlefield.ru/library/archi ... s4_02.html
http://www.battlefield.ru/library/archi ... s4_03.html )

No, the letter are not simultaneous. First answer, 3 days after Berias request (remember the deadline given?) is from Fedorenko and it favours beyond doubt the 122mm gun. The other 2 letters were sent 2 days afterwards. The most nuanced position belongs to Malyshev, but he was the superior of the other 2, therefore some degree of freedom can be expected from him considering his position.

But I note your doubt (read ignorance) regarding the pressure put on those engineers. You don't seem to be aware that many of those Russian engineers were doing their research while being actually imprisoned in the design bureau. After spending some years in Siberia, of course. Most of them came back from Siberia with chronic illnesses, a return there would have surely meant their death. By the way you talk about it, it is obvious to me that you were never subject of taking capital decisions regarding your and your family survival. Many people can take heroic decisions once or twice, but only a selected few can refuse colaboration if they are subject to daily threats and punishments, especially after their family suffered because of their decisions. Communists speculated this very well.

The September 12th letter you quoted seems completely unrelated to Berias request in August?
(and this is: http://www.battlefield.ru/library/archi ... pons5.html )

I'm not sure how good the translation of the document is, but I get the impression that they are saying that the max. range of the 100mm gun is 1500 meters, and at this range it penetrates. I dont think it is entirely clear whether it could in fact penetrate at longer ranges if the range of the gun was longer.
With regards to the 122mm, they say it penetrates at 2500m which is inside the maximum range of the gun and as such it is considered a valid result. But the report does not say that these results are conclusive, far from it. It is clearly stated that the results were preliminary and there are lot of ifs and buts about the results.

It appears to me that we do not read the same document. What ifs and buts are you talking about? The document clearly states that:

"This gun (122mm) reliably penetrates the Panther's frontal armor at 2500 metres, and that is less than its maximum range."

What does "reliable" means to you?

There are many other dubious things in this report, like the max (effective) range quoted for the 100mm gun: 1500m. The 100mm gun was an extremely powerful gun, how could it have only 1500m max range?

"The D-10 100 mm tank gun with ballistics identical to those of the BS-3 100 mm gun, its muzzle velocity being 890-900 m/s with a 15.6 kg projectile. This gun can penetrate the frontal armor of the Panther at up to 1500 metres, which is its maximum range."

This report has no credibility.

I wonder how ridiculous they can get. So they think the 100mm could penetrate Panther's glacis at 3000m, 3500m? what was the number?

You dont know? I would assume that you had to know Bird & Livingstones work to criticize it - particularily given your rigid view on "science" referred to at the beginning of this post......

They "proved" that the 122mm gun could penetrate Panther's glacis from 2500m, the 100mm gun was more powerful, so what should I expect other than another "out of this world" claim, 3500m fits here very well.

So my take on the infamous 2500mm Panther glacis penetration by 122mm APBC is that it may have happened vs a Panther with flawed armour, an old burnt out wreck, a tank already shot up or whatever, but it is not something that can be properly verified nor should one assume that it was something that would happen on a regular basis on the battlefield.

We agree here. Crews accounts tell us of instances when Panther and IS-2 penetrated each others glacis from around 600m. Considering that crews have a propensity to remember unusual occurrences, probably a certified penetration could have been achieved from 300-400m.

But it does not mean that the basic formulas Bird & Livingstone have published are rubbish, it means that a very small addendum to those formulas is dubious. And if you dont think the "Panther flawed armour" theory is any good, then just dont apply it when you use the formulas (I dont).

Like I said before, De Marre and alike formulas work very well when the projectile does not deform and the obliquity is not significant. Try them in other situations and all you'll get will be dubious estimations.

[Ultramagnus]

They "proved" that the 122mm gun could penetrate Panther's glacis from 2500m, the 100mm gun was more powerful, so what should I expect other than another "out of this world" claim, 3500m fits here very well.

Huck,I don't want to seem rude but what about reading their work first before criticize it? Page 88,first edition.

[cbo]

Please, don't put words in my mouth.

I'm not, I'm just drawing the logical consequences of what you are saying

I think we are dealing with a number of different issues here, so I'll try to make my position clear on each in turn:

1. WaPrüf tank-vs-tank documents and the Soviet document about the 2500m penetration of Panther glacis by 122mm gun:

By now, it should be clear to everyone what I have said. Penetration is far from being a deterministic process, we have probabilities associated with each penetration value. If the penetration values comming from different sources for a particular gun, ammo, armor plate hardness, distance and obliquity are in the vicinity of the mean value of the normal distribution that fits the original distribution of penetration values then we can consider those values as valid. If those penetration values are in a stark disagreement, being far from the mean value, we have to discard them as outliers. This is the case with the 122mm vs Panther glacis in German and Russian tests, both have to be rejected.

All that is old hat, Huck, we both know that

First of all, thanks for documenting that the Germans knew about the T/D ratio in WWII. That only makes the WaPrüf estimations even stranger......!

In my view, the "German tests" you are referring to are not tests, they are calculations based on known values about armour and penetration. Hence, they are not comparable to the Soviet document with the infamous 2500mm penetration of the Panther glacis by 122mm APBC which is an actual tank vs gun test. So, in my view, you are comparing apples and oranges.
The German results are uniformly overestimating the effects of slope, suggesting that there are something seriously wrong in their calculations.

2. Bird & Livingstons formulae
As for the Soviet September 1944 document describing the 2500mm penetration, you can choose to deal with it as a fraudulent document made by terrified engineers and discard it, as you suggest. Or you can assume that the test actually took place with the results described. I'll deal with that below.

But if you choose to believe it, you have to devise some kind of explanation for it. Bird & Livingstons results in their book clearly shows that such a penetration must have been some kind of anomaly, they say as much in their book (p. 88f). Their explanation is that there must have been something wrong with the Panther in question - its armour was flawed. They also note that variations in penetration could be due to some Panthers having face-hardened armour, others RHA.
Nowhere are they saying that a 2500mm penetration of the Panther glacis by 122mm APBC is the standard, expected result. How often it would happen would depend on how many flawed Panthers was out there.

They "proved" that the 122mm gun could penetrate Panther's glacis from 2500m, the 100mm gun was more powerful, so what should I expect other than another "out of this world" claim, 3500m fits here very well.

Where exactly did they "prove" this? Not in their book, as far as I can see...! So since you haven't read their book, you simply assume that they must be wrong and they would claim some outrageous figure for the 100mm gun..?

What they say in their book, is that this 2500m penetration could happen if there was something wrong with the Panthers armour quality. It could not happen if the Panthers armour was good quality.

I dont see anything wrong the approach made by Bird & Livingston (in their book) in this case, they are just trying to explain a peculiar result found in a primary source. I think their approach is a good deal more productive and in tune with the standards for historical research than simply discarding a document because it does not fit ones preconceptions (i.e. it is "obviously" wrong).

3. The interpretation of the August 1944 Soviet documents about the 100mm and 122mm guns
With regards to the August 1944 Soviet documents, by simultaneous, I mean they all appear to be related to the same request by Beria, made with only a few days between them.

And I'm not ignorant about the pressures that could be brought to bear on Soviet engineers, but I dont see it reflected in these documents.

Look at Federenkos reply to Beria (August 6th 1944):

It starts with:

To Comrade L.P.BERIA

According to your order about mounting the 100mm D-10T gun onto "JS" tanks, I have to say the following:

It seems that Beria was rather set on having the 100mm D-10T gun mounted in the JS...?

If Beria had given an order, then it would be rather silly of the scared-out-of-his hide engineer to argue against it, wouldn't it?

Yet, Federenko responds by a series of argument as to why the 122mm should be retained.

- The penetration of 122mm is good enough
- Adding another gun to the JS-series will cause problems with ammo supply
- 100mm HE is less effective than 122mm HE
- The difference between an ammo supply of 28 122mm or 29 100mm is of no importance
- The long 100mm rounds are difficult to handle in the turret of the JS and if the higher rate of fire is achieved, the additional fumes would handicap the crew and remove any advantages of a theoretical higher rate of fire with the 100mm.

All these seem completely valid reasons for retaining the 122mm gun in the JS. Were exactly do you see a scared engineer just aiming to please? And please who? Certainly not Beria, from the look of things!

Malyshev is in favour of the 100mm for a number of different reasons in his August 8th paper:

- it has a higher rate of fire
- with the 100mm the JS can tke one more round of ammunition
- with the 100mm gun, the JS will be 500-600 kg ligther
- as the 100mm gun is smaller, there will be more room in the turret
- the 100mm has superior penetration to the 122mm up to 2000 meters

These are also valid reasons (except perhaps the one about the ammo load...!), but different ones from those mentioned by Federenko. As I see it, this reflects different positions by different engineers to the same request/order from Beria. Unless you can somehow show that one of them was dragged before a firing squad or sent to work in a lead mine, I dont see how their alleged "fear" comes into play at all.

The last August 8th document to Ustinov takes a middle position:
- The rate of fire of the 100mm is higher, but trials have shown the 122mm to be quite good as well (4-6 RPM)
- They dont know if 100mm AP is immidiatly available

They then speak of the issues involved in their factorys switch from 122mm production to 100mm production, expecting to start producing 100mm guns in October 1944.

Again, where is the scared engineer? And who is he trying to please?

Sorry Huck, even though I'd agree that the working conditions for Soviet engineers was not enviable, I dont see anything here other than different positions on the issues involved in an immidiate switch from the 122mm to the 100mm gun in the JS-2.

If your conspiracy-to-please argument had any merit we wouldn't see different positions on this, would we? And none of these documents claim the 122mm to be the superior penetrator of armour, quite the contrary.

4. What does the September 1944 document actually say:

You write:

It appears to me that we do not read the same document. What ifs and buts are you talking about? The document clearly states that:

"This gun (122mm) reliably penetrates the Panther's frontal armor at 2500 metres, and that is less than its maximum range."

What does "reliable" means to you?

Just that. But you pick things out of the report without looking at the whole thing. They also say:

- The above test results are preliminary

- The method of evaluating armor penetration at angles of impact ranging from 0 to 30 degrees that is currently in use appears to be inefficient in evaluating the anti-tank guns.

- Therefore it is our opinion that it is necessary to reconsider the subject of the most effective caliber of the anti-tank guns.

- In this regard it appears that after the completion of the Kubinka tests, and if their final results confirm the current data, it would be beneficial to hold a special meeting to discuss further plans for the development of guns with high muzzle velocity.

It is plainly evident, that the results of the test conducted at Kubinka caused a good deal of concern about the validity of Soviet testing practices as a whole - the results achieved were puzzling even to those in charge of them.
Again, assuming they actually got the results described, their reaction is reasonable.

As for the issue of 1500 meters max. range for the 100mm gun, it could be any number of reasons, accuracy issues for example, like those experienced with the British 17pdr APDS and a host of other things. AFAIK there were still problems with the 100mm gun and ammo at this time, delaying the production of the SU-100 for several months.

Again, just because we dont know why they write as they do does not mean that we should simply discard it because we dont like what it says.

5. What crews tells us and What Bird and Livingston predicts

Crews accounts tell us of instances when Panther and IS-2 penetrated each others glacis from around 600m. Considering that crews have a propensity to remember unusual occurrences, probably a certified penetration could have been achieved from 300-400m.

That was a whole lot of assumptions in one bag

Since you dont know anything about the ammunition used, the part of the tank hit, the impact angles etc., this can hardly be used to prove or disprove anything. But it is not far from the Bird & Livingston formulae for 122mm APBC hit on flawless Panther glacis at 30 degrees....

Now, I think we have both made our positions clear. Unless something new emerges, I'm not inclined to proceed except that I'd like to know were you have picked up this idea that Bird & Livingstons formulae conforms with the September 1944 document on the 122mm firing tests at Kubinka.

Claus B

[WotS]

Can anyone post a pictures of T-44?
I have found only few in internet.

[Ace31]

Can anyone post a pictures of T-44?
I have found only few in internet.

Effectively there are very few pics on the Web about T-44, the best source is the link posted by Igorn (http://www.battlefield.ru/t44.html)


(the photo above from: http://homepage.eircom.net/~steven/sovarm.htm)

[WotS]

Thanks but i have seen it.

[HerrGeiger]

It is going to be quite hard to find pictures of the T-44 tank because the Soviet's weren't really giving about their information, or pictures of their tanks. But I would say that the T-44 would easily work the Panther tank in most ways. The Sherman was able to out due the Panther, so I think the T-44 can out due the Panther.