USA and German Penentration Test RHA armor Quality..

Hi, I'm south korean,
In Our nation's military history forum and people's thinking about both nation's test plate are "German test plate was 10~20% more powerful than USA test plate because German's Steel tech was higher than others".

But, I think that These view do not have enough evidence.

So I found information about this issue. But I could not find decisive evidence of "what is true?".

Somebody said "German gun target hardness(BHN) was higher than USA's, so German test plate was more resistance"

I think Only BHN can not be Basis of stronger plate.(T-34's High BHN armor But It was not stronger than german plate)

I found that USA's test plate was navy Standard armor "B". and 30 degree plate penentration data of German and USA gun in diffrent test condition.

For finding truth, I need "Table of 30 degree same plate(EX: USA "B" armor) penentration Test of German and USA tank gun"

If I can see that data, I can compare "German plate's test data of german gun" with "USA Plate's test data of German gun" and Know Truth about "German test plate was more powerful, so USA penentration data must reduce 10~20%"

Can you say to me about this information?

sorry about my weak english...

 

Hi lemiel, and welcome to the forum.

I wont pretend to know the answer to your question, but I say as much as that it is still a lot of myths out there and that the lack of evidence is apparent.

From what I can tell, the 10% extra effective thickness of German armour is from a British study which on purpose over-estimated the quality of German armour.

The difference in quality is another matter, however, and this would change during the course of the war.

 

Hi lemiel

The reason the T-34's armor was 'less-resistant' was becaue it was very brittle, and of poor quality, and it would splinter on the inside when hit.

German test-plates were indeed of better quality than U.S. ones (Wich is well proven ! ). But there are many other factors that has to be taken into consideration when you try to determine armor-penetrations, such as 'Test criteria'.

The German test criteria was that 66% of the projectiles fired at the plate must 'completely' penetrate to be considderet a penetration.

U.S. test criteria was that 50% of the projectiles fired at the plate must 'Partly' penetrate the plate to be considderet a penetration.

U.S. test-plates were normally 230-250BHN, while German test-plates were normally 300-350BHN (But could reach a peak of 495BHN !).

Best regards, KBO.

 

hi.. thanks answer...

First It's saying about "german Number of firings that must achieve Penetration" and Ratio can be 50% or 66%

Jentz states that two-thirds of the firings must penetrate the target armour plate, but Robert Livingston is not so sure. He says: “The passage in Jentz ... (is) the only explicit reference to German penetration criteria I have found. This passage is awkwardly translated into English and may or may not refer to the actual penetration criteria ... I suspect the German penetration criteria were not as strict as we might suppose. I don't feel that the little passage in Jentz is sufficient evidence to make much of a statement of what the German criteria were, given the awkwardness of the translation.”


Second..
You said "T-34's problem ; Brittleness"
BHN cannot be only evidence in your opinion of T34,
Why German high BHN can be evidence?

I could not find German test plate's name, But I can find German navy Anti penetration Nickel RHA plate of high quality "WOTAN STARRHEIT".
This German Nickel RHA's BHN was higher than USA standard armor, But, Its ratio of "ELONGATION" and ratio of "REDUCTION IN AREA" were lower than USA standard armor..

I think that we must regard quality of ductile.

So BHN can not be only evidence of this issue.

so I need data in USA standard plate penentration of "captured german gun"

 

You are aware of that although Livingstones and Bird's book is a good reference, it was intended primarily for 'Wargamers', and Tom Jentz is regarded a tad more reliable when talking about German stats.


Also the T-34's armor was about 450BHN, but very brittle and of poor quality.

The Tiger I's armor would lie anywhere from 450-550BHN, and was of very good quality ! (The best armor put on a tank during WW2)

KBO

 

There were done some tests in Britain with German guns, and the results were much higher than German results with the same guns.

An example:

German tests with the 128mm L/55 gun against 30* sloped armor using APCBC/Pzgr.39/43: 500m=178mm / 1000m=167mm / 1500m=157mm / 2000m=148mm.

British tests with the 128mm L/55 gun against 30* sloped armor using APCBC/Pzgr39/43: 500m=215mm / 1000m=202mm / 1500m=190mm / 2000m=178mm.

KBO

 

That last test might well be the one Skua is talking about, in which the British overestimated the German gun's penetration (which may have had political reasons).

As far as I know, but I must admit I know this only from what was provided on this forum, the Germans used both different types of steel and harder types of steel for testing than the Americans. This gave widely different test results for the same gun and all it shows is how penetration is truly relative to the target; there can be no universal rule. Often people who favor German tanks of WW2 will pick American and British tests for their arguments to show how high the penetration really was, which can later be adjusted by taking German test results for the same gun into consideration.

There is also the problem of slant; some tests are carried out on a plate with a 30 degree slant, where others take a vertical plate. Other criteria are, as pointed out earlier, the Brinell Hardness of the armour, and the various treatments of the steel (RHA vs. FHA).

I'm sorry if this merely makes it more complicated for you, but all these things need to be considered...

 

to KBO

This plate information was written by Jents "Germany’s Tiger Tanks. VK45.02 to Tiger II: Design, Production & Modifications"

This information's resource is Book of Robert Livingston,
Jents used livingston's book.

E22 steel plate
Feb. 1943, 30~50mm (PzKpfw.III, PzKpfwIV) -> 279~324BHN
Feb. 1943, 55~80mm (PzKpfw.III, PzKpfwIV, Tiger) -> 266~311BHN
Jun. 1944, 85~120mm (only Tiger) -> 220~265BHN

PP793 steel plate
55~80mm (PzKpfwIV, Tiger), -> 294~338BHN

The Tiger I's armor would not lie anywhere from 450-550BHN.

Thank about information "tests in Britain with German guns"

But My target is Quality of USA and GERMAN... sorry..

 

to roel

Thanks about advice...

I must think about your advice..




My favorite advice of Sun Tzu: All Victory of Hundred battles is not Goodness of Goodness, Nonbattle victory is Goodness of goodness..

 

Yes it would, but only the top layer. The Tiger like almost every other German tank used FH armor, wich could lie between 450-550BHN, however the Armor behind this layer on the Tiger I was of much better quality than usually on German AFV's(wich you demonstrated on your table).

KBO

 

to kbo

Did your saying mean "Tiger used FH Armor?"

Nickel RHA armor of german(tiger's) can not be 450-550BHN. and Too High BHN is not High quality.

John W. Schaefer said, "Face hardness can be accomplished fairly easily with a process such as oven surface carburizing. While high face hardness will help the armor defeat glancing impacts from soft-steel slugs, it also will tend to face-crack on heavy impact."

 

At least his table was backed up by a source, KBO... There doesn't seem to be any reason not to belive that the Tiger's armour was only marginally tougher than that of the PanzerIV and earlier German tanks, unless of course you could give us a source to prove that.

Lemiel: I'm glad I could be of assistance to you, though I doubt it helps you much in getting actual data...

 

Yes.

As i said only the top layer was 450-550BHN, the layer behind it was around 265BHN (309BHN in 42) and of great quality. (The hard top layer was for shattering incoming projectiles)

Yes face-hardning might be easy to achieve, but there are several levels of quality in face-hardning. The U.S. demonstrated with their own FH armor prior WW2, but found their version ineffective. Later German versions were very effective(Especially against USSR projectiles).

KBO

 

My source is presumably the same as Lemiel's: "Bird and Livingston's book" and "Tom jentz's"

Have you read some of Miles Krogfus' AFV News article's Lemiel ?

KBO

 

to KBO

First. Face hardness was not very effective on western front.

"The purpose of the hardened face is to shatter an incoming projectile’s head before it can penetrate. The Germans found it resisted Soviet uncapped AP and APBC projectiles quite well, when the armour plate thickness was around the same size or not too badly overmatched by the projectile (such as Pz.Kpfw.IV 50mm front armour vs. Soviet 45mm or even 76mm AP or APBC). Britain and the USA tested projectiles against FH armour as a matter of course until about 1943, but rarely used it on production vehicles because of its relatively poor resistance to German APCBC in comparison to RHA. The Germans were faced with APC and APCBC from the Western allies only, not the Soviets, so their decision to use FH armour weakened their tanks against Western guns but strengthened them against Soviet guns."


Second, What is High Quality?

Only BHN? Briton's plate's BHN was High too. For recognizing your opinion, You must present German plate's ratio of "ELONGATION" and ratio of "REDUCTION IN AREA".

and, Although either Tiger FH armor or Its High quality were True, they can not be evidence "German test plate was 10%-20% stronger than USA test plate". Do you know "what was german Test plate"?

so I need information of "captured german gun penentration data on USA standard test condition"

 

U.S. FH armor and German FH armor are two different things (In terms of quality), but yes German FH armor was strongest against USSR projectiles, but was also strong against Western projectiles.
Note your quote qoutes "because of its relatively poor resistance to German APCBC in comparison to RHA"

The reason FH armor was ineffective against German APCBC projectiles was because of the German projectile's hardness (They were beyond shatter-gap).

A British experimental test-example:

British tests against homogeneous armor at 610 m/s impact velocity:

102mm penetration for German 75mm APCBC
90mm penetration for U.S. 76mm APCBC
75mm penetration for Russian 76mm APBC

U.S. penetration tests for Sherman 75mm indicate 89mm penetration at 610 m/s.


-US 76mm M62 APCBC had a noose hardness of 477-(627 BHN-late)
-Soviet 76mm BR350 B APBC had a noose hardness of 460-560 BHN
-German 75mm PzGr 39 APCBC had a noose hardness of 627+ BHN

The molecular-structure of the armor.

All the info i have states the Tiger-I had the best armor of any tank during WW2, thats all the info about that i can give you.

Also bear in mind that U.S. tests were carried out in 'Yards', whereas German tests carried out in 'Meters'. 2000m=2187y / 2000y=1828m And this also magnifies German penetration stats.

Compare U.S. test results with captured German guns, with German test-results with German guns, and you'll see the difference !

Most sources i have quote 300BHN as standard for German test-plates, others 265-275BHN, i would suspect the last to be from late 44-45 tests.

You don't own Bird & Livingston's book do you ? There you'll find the answer, wether its accurate or not, you be the judge.

Anyway here's some penetration stats from Bird and Livingston's book:

All data is for U.S. test-criteria against 240BHN armor plates at 0 degree's:

75mm Kwk42 L/70 APCBC: 500m=168mm / 1000m=149mm / 1500m=132mm / 2000m=116mm.

76mm M1A2 L/52 APCBC: 500m=116mm / 1000m=106mm / 1500m=89mm.

88mm Kwk36 L/56 APCBC: 500m=151mm / 1000m=138mm / 1500m=126mm / 2000m=116mm.

90mm M3 L/52 APCBC: 500m=150mm / 1000m=137mm / 1500m=125mm / 2000m=114mm.

90mm M3 L/52 'Late war T33 AP FH': 500m=182mm / 1000m=168mm / 1500m=155mm / 2000m=142mm.

88mm Kwk43 L/71 APCBC: 500m=219mm / 1000m=204mm / 1500m=190mm / 2000m=176mm.


Best regards, KBO.

 

First, You must see this

"The Germans were faced with APC and APCBC from the Western allies only, not the Soviets, so their decision to use FH armour weakened their tanks against Western guns but strengthened them against Soviet guns."

You saying mean German FH plate was High quality so It has not Brittle problem.
But Where evidence? Where ratio of "ELONGATION" and ratio of "REDUCTION IN AREA"?
You have not evidence about "german plate has not Brittle problem"

and Do you know "why FH armor was useful against AP, APBC?" FH armor was useful against AP, APC, But FH armor was weak against APC, APCBC because Brittle problem. It used to be shetter in WW2



Second I have seen same condition vertical penentration data of these before,
But It's not perfect basis for comparing

90mm M3 M82 late Vertical penetration Data
500m=164mm / 1000m=151mm / 1500m=138mm / 2000m=127mm

88mm Kwk43 Pzgr39/43 Vertical penentration Data
500m=219mm / 1000m=204mm / 1500m=190mm / 2000m=176mm

I compared "90mm M3 M82 late 30degree USA standard penentration data on Hunnicut's" with these vertical penentration data of M82 late.

Vertical data of M82late was 28% more than 30 degree at 500m, 26% at 1000m, 23% at 1500m, 23% at 2000m

and I compared "88mm Kwk43 Pzgr39/43 30degree German test penentration data on Jents" with these vertical penentration data of Same gun in USA standard.

Vertical data of Pzgr39/43 was 18% more than 30 degree at 500m, 23% at 1000m, 28% at 1500m, 33% at 2000m

These results can be "partical Basis" of "which test plate was stronger?" But not Perfect evidence. In 500m, USA standard "B" armor was stronger than German test plate, In 1000-1500m, Both resistences ware nearly the same, In 2000m and more, German test plate was more stronger. By the way, these results can be partical evidence "German plate had Brittle problem, so it could be shatter by Hihg KE"

and, On Diffrence between M82 late and Pzgr39/43.

In Self nation's 30 degree Test plate penentration condition, M82 late's Penentration data was 69% of Pzgr39/43 at 500m, 72% at 1000m, 76% at 1500m, 78% at 2000m

In Same USA standard Vertical test plate penentration condition, M82 late's Penentraion data was 74% of Pzgr39/43 at 500m, 74% at 1000m, 72% at 1500m, 72% at 2000m.

In same condition of test, Diffrence between "M82 late and Pzgr39/43" was lower than Diffrence of "diffrent condition" in near distance, In addition, we need to think about Your saying, "German definition of penentration was "perfect" penentration"

these results can be evidence of "German test plate's Brittle problem"

more Hardness and "Diffrence of In and out layer's Hardness" Help KE projectiles's shock wave make Plate be shetter"

and, Its Result can not Perfect evidence about this issue.
SO I need same conditon "30 degree USA plate" Captured german gun test's DATA

 

and I heard about Tiger's FH armor Issue
"Jents said That was not certificated on his book"

 

One more thing

-------------------
In same condition of test, Diffrence between "M82 late and Pzgr39/43" was lower than Diffrence of "diffrent condition" in near distance, In addition, we need to think about Your saying, "German definition of penentration was "perfect" penentration"
-------------------

If German test plate was more stronger and German definition of penentration was severe standard, These Diffrence must increase.

But Result was diffrent. But these results can not be perfect evidence of "USA test plate was same quality or stronger" because It's not result on same condition of 30 Degree.


Oh one more..

I heard "FH armor Tiger existed, But, RHA armor Tiger existed too. and In later war period, almost tiger had RHA armor"

 

I must admit I´m a bit confused, even though we have been through this before.

1. I thought that the Germans only used face hardened armour on some tanks ( PzKpfw III and PzKpfw IV comes to mind ) and in these cases only in certain positions ( front plates for example ).

2. Face hardened armour is, as far as I can tell, only an advantage to homogenous armour for as long as the weight and/or velocity of the projectile that hits it is not too high, then it becomes a disadvantage ( ie face hardened armour was no longer an advantage when guns as the 17pdr or even the American 76mm entered service ).

3. I find it odd that the Germans would be using exactly the same type of armour plates with the same BHN value on every type of tank they ever produced, as KBO gives the impression of.

4. BHN does not equal quality. The Soviets produced armour plates with higher BHN values than the Germans, but these plates proved to be very brittle.

5. What about alloys ? Alloys were used to give armour plates more strenght.

KBO, we´ll be turning in circles again unless you give us some decent sources for your claims. Personally I don´t think Jentz can be trusted when we move into the world of metallurgy.