T-34 frontal armor vs 50mm kwk 38 or 39 L/60

[Username]

http://home.comcast.net/~markconrad/10TD1941.html

Very interesting read considering the early time frame and Soviet perspective.

TECHNICAL REPORT FROM THE 10th TANK DIVISION, AUGUST 1941

[The original Russian transcript came to me from Mr. Charles Sharp. It is a report signed by the commander of the 10th Tank Division, dated 2 August 1941.)
\

The division’s soldiers and commanders spoke of their tanks as very reliable machines. But along with these qualities they had the following defects:

1) For the KV tanks:

a) Under the impact of shells and large-caliber bullets, the turret ring and armored cupolas can jam.

b) The diesel engine has little reserve power, resulting in it being overloaded and overheating.

c) The main and side clutches break down.

2. For the T-34:

a) Hull armor is penetrated at 300 to 400 meters by a 37-mm antitank round. Side armor is penetrated by a 20-mm antitank round. When crossing ditches the low set of the vehicle causes its nose to dig in, and traction with the ground is insufficient due to the relative smoothness of the tracks.

b) With a direct hit by a shell the driver’s front hatch collapses.

c) The vehicle’s treads are weak—any round takes them off.

d) The main and side clutches break down.

[Contender]

Ty m8 very good work.
This is the only thing I find issue with:

Because the 5 cm KwK can only be expected to penetrate the flanks of the T34 at short range, the following tactics have proven been to be correct in combating them...:

Because it does not specify which 5cm Kwk it could be the L/42.

[frcoplan]

Not entirely linked to this thread, but you might find some data on this link from tanknet usefull:

http://www.tank-net.org/forums/lofivers ... 18562.html

frcoplan

[Art]

Here are some data collected by specialists from the People's Commissariat for Tank Industry as a result of examination of damaged T-34 tank in several repair workshops in August-September 1942. In all they examined 154 knocked-out T-34 which had 534 shell "hits". Of the total number of hits 289 or 54% were safe, that means they were not accompanied by armor penetration and 245 were "dangerous" (armor was penetrated). About 54% of the total number of hits were caused by 50-mm shells, the ratio of safe to dangerous hits was 57%/43%. Just for comparison the same ratio for hits caused by 20-37-mm shells was 68/32, for 75-mm - 31/69. for 88-mm - 5/95. 89 hits in the upper front detail were examined, of them 35% or about one third were caused by 50-mm shells. These hits were for the most part safe, only in 11% of cases the armor was penatrated. In the lower front detail there were 12 hits - too few to make reliable statistics, of them 3 caused by 50-mm shels (1 safe and 2 dangerous). 123 hits were in the vertical side plates, of them 88 from 50-mm shells (34 safe and 54 dangerous). In the sloped side plates - 147, of them 94 from 50-mm shells (69 safe and 25 dangerous). It's obvious that vertical armor plates were more easily penetrated than sloped. which is. of course, quite natural. Rear details had 40 hist distributed in the following way - 21 in the upper rear detail (4 safe and 6 dangerous from 50-mm shells), 19 in the lower rear detail (5 safe and 4 dangerous from 50-mm). Turrets had 102 hits, in most cases 50-mm shells penentrated armor.
In all 50-mm shells caused 54,3 % of all hits, 60% of safe hits, and 51,6 % of dangerous. In other words 50-mm guns were the main cause of T-34 losses of that period. The general conclusion is that the front armor of T-34 was a more or less reliable protection against German 50-mm guns, while sides and turret could be penetrated in a singnificant percentage of cases and for the most part T-34s were knocked out by such type of hits. It must be mentioned that the report says that no cases of use of 50-mm subcaliber ( APC) shells were registered. Then it doesn't separate various types of 50-mm guns (Pak-38 and KWKs). It is worth to mention that a statistically significant number of penetrations were cuased by shells with caliber smaller than 50-mm, which is in contrast with usual idea that T-34 was somehow ipregnable against them.
The scan of the report can be found here (in Russian):
http://litl-bro.livejournal.com/1700.html

[GaryD]

The scan of the report can be found here (in Russian):
http://litl-bro.livejournal.com/1700.html

Great link!

[Art]

Great link!

Oh, yes. Well, continuing to explore the same resource, that is from is from the report entitled “Study of penetration action of German trophy projectiles on our tanks’ armor and development of measures for struggle against them”, printed in January 1943.
Diagram of penetration capabilities of German 37- and 50-mm and Soviet 37- and 45-mm shells against 45-mm high hardness armor (distance from wich the plate is penetrated versus incidence angle) baes on results of trials:

As one might see 45-mm armor plate, equivalent to the ones T-34 hull was made of, can be penetrated from about 2000 meters at reailstic angles. It's interesting that "subcaliber" (APCR) projectiles demonstrated worse penetration capabilities then usual AP shells. It's worth to note that Soviet 45-mm shells turned out to be less potent in terms of penetration capabilities then German 37-mm, not to speak of 50-mm. The report's authors made the folowing conclusions based on this diagram:

Tactical diagram of the T-34 hull shows that the tank is well protected against German 37-mm and 50-mm artillery from the front, which can be penetrated in exceptional cases only (as a result of a tank’s tilt on terrain roughness).
“Podkrylky” (side sloped plates) can be penetrated by 50-mm guns only, dangerous hits zone being considerably larger for AP shell then for subcaliber (APCR) shell.
Tank’s sides are the most vulnerable details and are penetrated by both 50-mm and 37-mm guns, 50-mm shells having the most effective action, especially AP shells. 37-mm shells don’t yield through penetrations, although by penetration limit they are more effective than subcaliber shells.
The tank’s rear is penetrated by 50-mm guns only, and the largest zone of dangerous hits corresponds to AP shells.
Confirmation of the calculated tactical diagram can be seen from the results of T-34’s hull tests made on the Gorokhovets artillery proving ground by the #112 factory, the hull was made of MZ-5 grade steel, due to similar shells protection capabilities that is equivalent to serial hull’s tests.
Fire tests were made from the distance of 50 meters with AP and subcaliber shells from German 37-mm and 50-mm guns and a domestic 45-mm gun.
The principal results of the tests are given in the table from which it might be seen that:
1) The upper front detail due to large slope is not penetrated by German antitank gun shells of 37 and 50-mm caliber.
2) “Podkrylky” (sloped side plates) can be penetrated by German 50-mm antitank gun shells and are not penetrated by the 37-mm gun.
3) Side details are penetrated by 37- and 50-mm German guns.
4) Rear details are penetrated by the 50-mm gun (no tests with the 37-mm gun were made)
5) Cast turret is penetrated by 37- and 50-mm guns.
However, penetrations of the T-34 in actual combat conditions can not fully correspond to the results presented above, because shell hits while the tank is moving especially on a rough terrain will naturally occur by different angles than in stationary conditions.
General results of the test fully confirm conclusions following from examination of the tactical diagram of T-34 armor protection.

[Alejandro_]

Great info Art. IIRC that document also talk about lighter tanks and KV. Can anyone summarise what is mentioned about KV-1?

P.S I have translated a text from Russian to English. A few phrases need to be corrected. If anyone could help it would be very kind. It should not take too long to do.

[Paul_Atreides]

What phrases?

[Alejandro_]

Edited by the author. Denis translated them. Thanks.

[Art]

IIRC that document also talk about lighter tanks and KV. Can anyone summarise what is mentioned about KV-1?

Ok.

[Art]

Well, about KV. The report says that there are no data about vulnerability of KV as detailed as about T-34, which was partly due to desire to collect data concerning the new model (apparently KV-1S), production of which just started.
As concerns the old KV with 75-mm sick armor of 226 shell hits 38,5% fell on the turret, and 61,5% on the hull. 3,5% of studied tanks were disabled by mines, 4,5% - by fires. No penetrations were made by shell with caliber below 50-mm, 9,5% - by 50-mm AP shells, 37% - by 50-mm subcaliber, 41 % - by 88-mm and 67% - by 105-mm AP shells. The last number seems suspicious, probably it’s a misprint and they mean 6,5.
According to tactical diagram based on results of test 37-mm AP shells could not penetrate the armor of KV, subcaliber shells penetrated sides and rear from a distance of less than 200 meters under favorable angles, front details were invulnerable. 50-mm subcaliber shell penetrated sides from a distance 750-850 meters (according to different criteria of penetration), AP shell – from a distance of 400-700 meters. The results for rear armor details were generally the same (I simply can’t discern distance scale on the low quality picture). The front armor was invulnerable to 50-mm AP shells, but was penetrated by subcaliber shells from <500 m distance.

[Alejandro_]

Thanks Art.

According to tactical diagram based on results of test 37-mm AP shells could not penetrate the armor of KV, subcaliber shells penetrated sides and rear from a distance of less than 200 meters under favorable angles,

This is expected when compared to T-34, even if equivalent armour (slope+thickness) is rather similar. KV-1 frontal armour could withstand 76mm F-34 hits from short range, which penetrated T-34.

[LachenKrieg]

Here are some data collected by specialists from the People's Commissariat for Tank Industry as a result of examination of damaged T-34 tank in several repair workshops in August-September 1942. In all they examined 154 knocked-out T-34 which had 534 shell "hits". Of the total number of hits 289 or 54% were safe, that means they were not accompanied by armor penetration and 245 were "dangerous" (armor was penetrated). About 54% of the total number of hits were caused by 50-mm shells, the ratio of safe to dangerous hits was 57%/43%. Just for comparison the same ratio for hits caused by 20-37-mm shells was 68/32, for 75-mm - 31/69. for 88-mm - 5/95. 89 hits in the upper front detail were examined, of them 35% or about one third were caused by 50-mm shells. These hits were for the most part safe, only in 11% of cases the armor was penatrated. In the lower front detail there were 12 hits - too few to make reliable statistics, of them 3 caused by 50-mm shels (1 safe and 2 dangerous). 123 hits were in the vertical side plates, of them 88 from 50-mm shells (34 safe and 54 dangerous). In the sloped side plates - 147, of them 94 from 50-mm shells (69 safe and 25 dangerous). It's obvious that vertical armor plates were more easily penetrated than sloped. which is. of course, quite natural. Rear details had 40 hist distributed in the following way - 21 in the upper rear detail (4 safe and 6 dangerous from 50-mm shells), 19 in the lower rear detail (5 safe and 4 dangerous from 50-mm). Turrets had 102 hits, in most cases 50-mm shells penentrated armor.
In all 50-mm shells caused 54,3 % of all hits, 60% of safe hits, and 51,6 % of dangerous. In other words 50-mm guns were the main cause of T-34 losses of that period. The general conclusion is that the front armor of T-34 was a more or less reliable protection against German 50-mm guns, while sides and turret could be penetrated in a singnificant percentage of cases and for the most part T-34s were knocked out by such type of hits. It must be mentioned that the report says that no cases of use of 50-mm subcaliber ( APC) shells were registered. Then it doesn't separate various types of 50-mm guns (Pak-38 and KWKs). It is worth to mention that a statistically significant number of penetrations were cuased by shells with caliber smaller than 50-mm, which is in contrast with usual idea that T-34 was somehow ipregnable against them.
The scan of the report can be found here (in Russian):
http://litl-bro.livejournal.com/1700.html

I am currently interested in the topic of battle effectiveness of the 50mm L/60 gun mounted on the PzIII M against T-34/Sherman tanks, and found this thread to be a very interesting read. The discussion still leaves room for questions though, and I was hoping that anyone with more insight on this topic might be able to provide some of the answers for me.

To start, the above bold text states that of the 89 hits to the upper front detail that were examined, approximately 30 of them were caused by 50-mm shells. Is the 11% of cases where penetrations occurred referring to 11% of the 50-mm hits, or the 11% of the total number of hits on the front detail?

[Peasant]

89 hits in the upper front detail were examined, of them 35% or about one third were caused by 50-mm shells. These hits were for the most part safe, only in 11% of cases the armor was penatrated.

I am currently interested in the topic of battle effectiveness of the 50mm L/60 gun mounted on the PzIII M against T-34/Sherman tanks, and found this thread to be a very interesting read. The discussion still leaves room for questions though, and I was hoping that anyone with more insight on this topic might be able to provide some of the answers for me.

To start, the above bold text states that of the 89 hits to the upper front detail that were examined, approximately 30 of them were caused by 50-mm shells. Is the 11% of cases where penetrations occurred referring to 11% of the 50-mm hits, or the 11% of the total number of hits on the front detail?

The immunity of the UFP of T-34 under attack from german 50mm AT guns was established to a quite high degree of confidence by ballistic trials of separate armor plates as well as a shelling of an assembled hull taken from mass production. The author of the original document suggests that explanation might be that because of the irregularities of terrain, T-34 can sometimes present this part under angle less than 60°, allowing for perforations to occur.

Still, I believe, it doesn't necessarily mean this was the reason for every single perforation that happened. Its not unlikely that some of the soviet tanks, especially those produced that year (1942) could've had sub-standard armour plates installed in them.

[LachenKrieg]

89 hits in the upper front detail were examined, of them 35% or about one third were caused by 50-mm shells. These hits were for the most part safe, only in 11% of cases the armor was penatrated.

I am currently interested in the topic of battle effectiveness of the 50mm L/60 gun mounted on the PzIII M against T-34/Sherman tanks, and found this thread to be a very interesting read. The discussion still leaves room for questions though, and I was hoping that anyone with more insight on this topic might be able to provide some of the answers for me.

To start, the above bold text states that of the 89 hits to the upper front detail that were examined, approximately 30 of them were caused by 50-mm shells. Is the 11% of cases where penetrations occurred referring to 11% of the 50-mm hits, or the 11% of the total number of hits on the front detail?

The immunity of the UFP of T-34 under attack from german 50mm AT guns was established to a quite high degree of confidence by ballistic trials of separate armor plates as well as a shelling of an assembled hull taken from mass production. The author of the original document suggests that explanation might be that because of the irregularities of terrain, T-34 can sometimes present this part under angle less than 60°, allowing for perforations to occur.

Still, I believe, it doesn't necessarily mean this was the reason for every single perforation that happened. Its not unlikely that some of the soviet tanks, especially those produced that year (1942) could've had sub-standard armour plates installed in them.

Thanks for your reply.

I couldn't agree more. And not just because theoretical calculations for expected outcomes can for the most part be reproduced under test conditions, but because I believe the suggestion being made by the OP to this thread is also valid.

For completeness, irregularities in terrain could also mean that the 50mm AT gun was attacking from a slightly elevated position as an explanation to changes in the angle of attack. And your suggestion that the quality of mass-produced Russian armor might have been an issue is probably more then just an assumption considering the volume produced, and the number of sites involved. We could also add to the list the effect of multiple shots striking the same area. Both the armor thickness and its strength can be altered with each successive hit.

The point is, if we go by the evidence available, it appears that both the Pak 38 and 50mm L/60 were responsible for frontal penetrations on T-34 Russian tanks. It is most certain that these penetrations had to occur at close range, but in my view this particular discussion point often gets confused between what should have been, and what appears to have happened.

Case in point, as a contributor to this discussion, cbo has made a very valid argument based on the theoretical calculations that have also been confirmed under test conditions. But other then accepting that 30 degrees form the vertical is the same as 60 degrees from the horizontal, his/her argument fails only in that it does not recognize actual history on the matter.

My interest here is to gather and review that historical information. If anyone has a source of actual battle accounts involving the German 50mm At gun and T-34 tank, I would really appreciate it.