Best Tank of WW2

[dunmunro1]

So the Hull side is also curved? It was also penetrated by the 6 pdr APCBC at 30deg target angle. Again impossible according to your data. The 30 deg Target angle for both the Turret and the Hull is clearly stated.

Also why did the Brits test their guns in the USA at Aberdeen? Why the variation in armour type for the two different tests?

 

[Juha]

Soren
Do you really think that British were incapable to measure hit angles in their tests?
If you bothered to look the scan you'll see that the other angles are given with exact angle but the turret side as approx. 30deg. So the British noticed that turret sides of Tiger were a bit like horseshoe.
And it was a test against real Tiger, and I believe more on tests made against real targets.

The Pak 39 figures were probably calculated, they were from Zaloga's Hetzer book, he gives as the source Wa Prüf 1 report dated 5 Oct 44. Have you figures from actual tests against Cromwell, Spielberger's Czech Tank book had one graph which showed Hetzer and PzIV/70(V) vs several types of Allied and Soviet tanks, but again it isn't clear how the figures were got.

On real test results, British tests against real panzern in North Africa showed that 6pdr penetrates 50mm FH turret front of PzIV from 800m and driver's plate from 900m. Source Jentz' Panzertruppen Vol 1.
Ammo not mentioned but probably plain AP. Later APC penetrated better and still later APCBC clearly better.

So to clarify my claim, depending the 57mm fullbore ammo used, Cromwell could penetrated the turret of Pz IVH-J farther, about same distance or from shorter distance than PZIV could penetrate its turret with PzGr. 39.

On mobility of Pz IVJ vs Charioteer. Now I have read, admittedly a long time ago, on Finns experiences with Pz IVJ, 25ton tank with 272hp engine and have sawn and ridden on Charioteer on same kind of terrain, albeit only in winter, during our summer manoeuvres other side's light infantry kept us very occupied. IIRC Charioteer was as heavy or a bit heavier than Cromwell, which was 28ton tank with 570bhp engine. Now at least Charioteer didn't give impression of underpowered tank with oldfashioned suspension.

Juha

 

[Soren]

So the Hull side is also curved? It was also penetrated by the 6 pdr APCBC at 30deg target angle. Again impossible according to your data. The 30 deg Target angle for both the Turret and the Hull is clearly stated.

Listen dunmunro it is not MY data, it is the official British tests with the gun. So unless you believe the British somehow got their own figures wrong after hundreds of firing tests done to establish the average penetration performance then I really don't see a problem here.

Problem with the paper you presented is we know no other parameters than the angle upon which was opened fire and the range. At right angles the 6pdr could defeat 102mm of 240 BHN armour at 600y, so if it struck at around 20 degrees on the Tiger's side turret hull it would've been likely to penetrate.

There could also be anothe reason for the result; If the Tiger's side armour was face hardened, this would've worked well against uncapped projectile but poorer against the by then modern capped APCBC rounds. I do know that the Tiger's front armour wasn't face hardened, but IIRC the sides actually were. This practice was however discontinued in 1944 as the Soviets started using capped AP rounds in mass.

Also why did the Brits test their guns in the USA at Aberdeen? Why the variation in armour type for the two different tests?

The British didn't test their guns at Aberdeen, the Americans did. The Americans brought German, British, Soviet and even Italian guns over for testing to assess the effectiveness of each gun and learn from it. The Brits made their owns tests with US, German Soviet guns for the same reasons, as did the Germans.

 

[Soren]

Soren
Do you really think that British were incapable to measure hit angles in their tests?
If you bothered to look the scan you'll see that the other angles are given with exact angle but the turret side as approx. 30deg. So the British noticed that turret sides of Tiger were a bit like horseshoe.
And it was a test against real Tiger, and I believe more on tests made against real targets.

The Pak 39 figures were probably calculated, they were from Zaloga's Hetzer book, he gives as the source Wa Prüf 1 report dated 5 Oct 44. Have you figures from actual tests against Cromwell, Spielberger's Czech Tank book had one graph which showed Hetzer and PzIV/70(V) vs several types of Allied and Soviet tanks, but again it isn't clear how the figures were got.

On real test results, British tests against real panzern in North Africa showed that 6pdr penetrates 50mm FH turret front of PzIV from 800m and driver's plate from 900m. Source Jentz' Panzertruppen Vol 1.
Ammo not mentioned but probably plain AP. Later APC penetrated better and still later APCBC clearly better.

So to clarify my claim, depending the 57mm fullbore ammo used, Cromwell could penetrated the turret of Pz IVH-J farther, about same distance or from shorter distance than PZIV could penetrate its turret with PzGr. 39.

On mobility of Pz IVJ vs Charioteer. Now I have read, admittedly a long time ago, on Finns experiences with Pz IVJ, 25ton tank with 272hp engine and have sawn and ridden on Charioteer on same kind of terrain, albeit only in winter, during our summer manoeuvres other side's light infantry kept us very occupied. IIRC Charioteer was as heavy or a bit heavier than Cromwell, which was 28ton tank with 570bhp engine. Now at least Charioteer didn't give impression of underpowered tank with oldfashioned suspension.

Juha

As I told Dunmunro I believe face hardening is the answer to the results of the British tests. The Germans face hardened armour of ~85mm below to increase its effectiveness against uncapped enemy AP projectiles. The Soviets mostly used uncapped solid shot AP projectiles up until around some time in 1943, and FH armour was very effective against these, often shattering the projectiles which in theory should've penetrated. But by late 1943 onwards the Soviets started using capped APprojectiles in mass and as a result the Germans discontinued the practice of face hardening their armour at around late 1943 to early 1944. The point here being that the 5.7cm APCBC projectile of he 6pdr would've had an easier time against face hardened armour than just plain RHA, which would explain the results against the Tiger in 1943.

The first Panther's featured FH armour as-well.

 

[dunmunro1]

US Army testing of 57mm AT gun against captured Panther:

"The gun was moved to a new position of 300 yds range at an 8 degree angle off the front of the tank. Three rounds were fired into the front of the tank. These rounds made slight penetrations then ricocheted off the frontal armor. Two rounds were fired into the turret—one made a clean hole, the other mad a hole about three inches in diameter. No fires were started. Two rounds were fired low on the track, these went through the bogie wheels on one side and came through tore up the bogie wheel and track on the other side of the tank. Two rounds were fired into the front driving sprocket and the track was broken. All but one round fired from this position, which was a bad frontal angle, made clean holes, with the exception of the three fired on the frontal armor, which made only slight penetration."
57mm AT Gun

The Turret Armour = 110mm at 8deg...again impossible to penetrate according to your data.

 

[Juha]

One point
British 6pdrs, both A/T and tank guns were either L/43 or L/50 type, also ammo development was constant. So both shots and mvs varied according to shot type and barrel leght.

Juha

 

[vinnye]

I think this article is a little optimistic in saying the Tiger was eliminated! It does not say at what range the shot was fired and how many Churchills attacked the Tiger (and how many were lost?).
I have seen the Tiger at Bovington and you can see the goue made by the round on the gun barrel.

View: https://www.youtube.com/watch?v=BD9UdQxE70c

 

[Soren]

Dunmunro, the Panther's front turret armour is 100mm thick, not 110mm. The mantlet is 110mm thick. But even then the 6pdr proved capable of defeating that a 300yards, penetrating 115mm of vertical 240 BHN RHA armour at 300yards in US tests at Aberdeen. At a 8 degree side angle the figure only decreases by about 4 to 5mm, and th Panther wasn't known to have the best quality armour, sometimes featuring 212 BHN RHA armour. So again, no the test results I presented do NOT say it was impossible, quite the opposite infact. So stop your whining an read what is being written before you respond!

 

[fastmongrel]

D So stop your whining an read what is being written before you respond!

Thats a bit uncalled for do you really need to be rude. He has a different view of the evidence which he is allowed to have.

 

[Soren]

Thats a bit uncalled for do you really need to be rude. He has a different view of the evidence which he is allowed to have.

He was practically saying I was making stuff up, and thats rude. Instead of saying that "according to your stats thats impossible!" over and over again he could've simply read what I wrote, and if he still disagreed he could said it in a calm manner. What he doesn't seem to understand is that all British tests have been taken into account in Livingston Bird's book, and that includes the ones he just posted.

 

[Juha]

Hello Soren
But why in in Livingston Bird's book test results for British guns are poorer than in original British tests, especially at longer ranges? What is their explanation? After all British criteria was a bit more strict than the US one. And it's odd that their result for 17pdr against homogeneous armour is the same as British results against FH and poorer than British result against homogeneous as shown by the scan in the other tread.

And the Panther's mantlet was 100mm, all sources seemed to agree with that, the turret front was 100mm or 110mm depending on source.

Juha

 

[Vincenzo]

for Panther turret front i think there was a change the D had 100 A G 110

 

[Juha]

Hello Vinzenco
that how it is in some sources but according to Jentz' Panther book also G had 100mm turret front.


Hello Soren and Vinzenco
and the 77mm penetration table that Soren gave in the other tread is comparable to the British tests, so at 30deg homo.
120mm@500y 110mm@1000y 100mm@1500y 90mm@2000y

Juha

 

[dunmunro1]

Soren, you're not making stuff up, but you are attempting to take one data set and proclaim that it is 100% accurate. Every time data is brought to your attention showing actual performance being better than the data your present, you then try to present an implausible argument explaining the discrepancy.

For example, the US Army fires two 57mm APCBC rounds at 300 yds and 8 degs target angle, into the turret front and almost certainly these hit the 115mm mantlet of the Panther (it is almost impossible to miss the mantlet on a panther) and cleanly penetrated it...an amazing result if the gun is right at its critical velocity for penetration! The data I presented in the WW2 Tank gun thread, shows the 6 Pdr APCBC penetrating 102mm at 10deg at 2400fps on an actual tank target, and this would be equivalent to a range of ~1000 yds.

edit: The mantlet thickness seems to vary from source to source. Here's what I used, but I note that it is 110mm not 115mm:
FileantheraScheme.jpg - Wikipedia, the free encyclopedia

 

[Vincenzo]

mantlet of panther it's 100 i think all source are agree on this, as told to juha.

 

[dunmunro1]

mantlet of panther it's 100 i think all source are agree on this, as told to juha.

Sorry, I edited my last post before your reply.

 

[Soren]

Hello Soren
But why in in Livingston Bird's book test results for British guns are poorer than in original British tests, especially at longer ranges? What is their explanation? After all British criteria was a bit more strict than the US one. And it's odd that their result for 17pdr against homogeneous armour is the same as British results against FH and poorer than British result against homogeneous as shown by the scan in the other tread.

And the Panther's mantlet was 100mm, all sources seemed to agree with that, the turret front was 100mm or 110mm depending on source.

Juha

Well Juha what's strange is that Dunmunro claims the figures listed under "C" are against FH armour and the results against this are worse. In reality APCBC projectiles behave better against FH armour than pure RHA. So the only explanation for the figures is that they weren't obtained with the Mk.8T APCBC projectile, but some other projectile, AP, APBC or APDS.

Here's the 17 pdr performance against plain 240 RHA vs Face hardened 240 RHA plates (From the book WW2 Amor Gunnery):

As you can see the APCBC's performance increases against FH armour and declines vs pure RHA, where'as it's the other way round for the plain AP projectiles.

Here's what Livingston has to say on the matter:

Face Hardened armor is best at defeating uncapped AP when it overmatches
the projectile, that is, the diameter of the round is less than the
thickness of the armor. Caps on APC and APCBC defeat FH by encouraging
crack formation in the hard brittle surface. The nose of the round is
supported by the cap during the impact stage of penetration. The cap
blows out of the way for the rest of the trip through, with penetration
either by deepening cracks and ejection of material (plugging), or by
"ductile push-aside". FH tank armor generally had 80-95% of its depth at
machinable homogeneous levels. It was, in fact, made out of RHA. You can
see why it was more expensive as it took time, materials, and other
effort. After the additional heat treating, the plates tended to curl,
and so were flattened cold in presses. This cold-working introduced
locked up stresses which could be relieved catastrophically under
ballistic impact.

Homogeneous armor was "the best" by the end of WWII, when 3-6+" thick.
Even so, the Germans had considerable industrial plant dedicated to
production of FH plate, some made by the novel method of induction
hardening. People ask why the Pz III and IV remained in production too
long, to which we should add that much of their plate was expensive to
produce and difficult to assemble. Against uncapped Russian small bore,
capless AP and APBC (ballistic windshield only) it probably worked well.
These weapons were more likely to hit the Panzers than the
76-85-100-122s, due to the quantities of 45s and 14.5s on the field.

Rolled armor is ballistically superior to cast armor due to the
compaction and consolidation of grain structure which occurs during
rolling. Rolled armor is made directly from cast ingots, so you an see
that cast armor could be cheaper, as it dispenses with a huge and costly
step in fabrication. Mold making cost offsets this, but in mass
production allows savings on long term pattern use. The USA pioneered
cast armor during WWII, taking the lead from the French with their S-35s
and all. We had developed big casting techniques for for our locomotives
a good decade earlier.

Cast hulls and turrets can easily be curved, which results in less
exterior surface area for the same volume enclosed (the igloo principle).
Cast hull Shermans were good at taking glancing hits on the curved sides.
The armor was soft and ductile, and photos don't usually show cracks in
punctured Shermans. Cast armor was subject to poorly controlled
thickness, resulting in oddities such as 44mm M4A1 hull sides as measured
by the Germans 38mm nominal thicknes), and 2" rather than 3" inner gun
shields found on an early/mid M4A3. Crystalline grain structure up
through 11/43 limited ballistic resistance of cast and rolled US plate.

He also has this to say about German projectiles tests, as-well as some info on the late war Panthers:

At the beginning of the war the Germans tested French and British armor
as found on captured tanks at Dieppe and in N. France, finding it
comparable to German armor. By the end of the war the US had tested
German projectiles and found them significantly better than ours, against
our own and British plates. As their penetration data for their own guns
showed, the Germans were able to make VERY resistant plates through to the
end of the war for their own test programs. The quality of AFV
production armor suffered, though. The loss of nickel and molybdenum
supplies was critical, and they could only compensate successfully on a
proportion of the plates delivered, due to the finicky and troublesome
interrupted-quench system, wherein plates were hoisted in and out and
back into huge quench pools, with timing to the nearest second. I
believe the Panther glacis often was defeated at the mill, with a 10-20%
reduction in effective thickness due to incorrect quenching and
tempering. A metallurgical report on a Panther glacis showed the
presence of bainite, a crystalline form of steel, in an interior layer
(like plywood).

 

[Juha]

Hello Soren
Thanks for posting the info even if I was aware of that before. IMHO the problem is that 17pdr shot didn't overmatch the plates in question, they being thicker than 76,2mm. On German ammo, on one message to one board Lorrin wrote that because only very small % was proof tested, of those captured ones which Allied tested most were under specs, which were very high, higher than Allied ones, some even so much that they should have had rejected.

Juha

 

[Soren]

Updated my response Juha

 

[dunmunro1]

Well Juha what's strange is that Dunmunro claims the figures listed under "C" are against FH armour and the results against this are worse. In reality APCBC rounds behave better against FH armour than pure RHA. So the only explanation for the figures is that they weren't obtained with the Mk.8T APCBC projectile, but some other projectile, AP, APBC or APDS.

C =cemented armour, which is another way of stating face hardened armour. Once again you launch into an improbable explanation for results that challenge the data you are presenting.