Wednesday 22 November 2017

8.8 cm KwK 36 Trials

"B. Firing on KV-1 and T-34 hulls with the 88 mm gun

1. Firing on a KV-1 hull.

The KV-1 hull was fired upon with armour piercing and high explosive rounds from 1500 meters. The results are shown in table 2.

Table 2

Target
Shell type
Armour thickness
Armour slope
Impact angle
Damage
Front hull appliqué armour
AP
20
20
70
20 mm deep dent. The shell ricocheted into the corner of the driver's plate appliqué armour and chipped off a section 120 x 110 mm.
Turret rear
AP
75
20
70
Complete penetration. Entrance: 120 x 110 mm, exit 190 x 130 mm.
Turret rear
AP
75
20
70
110 x 90 mm armour fragment torn off.
Applique armour and driver's plate
AP
75+30
20
70
Complete penetration, entrance: 110 x 130 mm, exit 180 x 210 mm. 230 x 210 mm section torn off the appliqué armour, two 200-270 mm cracks formed in the appliqué armour.
Driver's plate appliqué armour
HE
30
20
70
Right section of the appliqué armour torn off (section weakened by hit #4)
.

Photo #4. Overall view of the KV-1 hull after being fired upon by the German 88 mm tank gun.

Photo #5. Impact of the armour piercing shell to the front hull applique armour. 20 mm deep dent. The shell ricocheted into the driver's plate and knocked off a 120 x 110 mm section.

13 comments:

  1. Note that the angles reported do not fit with the KV1 hull geometry. Both, hull nose and driver plate were declined 30°, not 20°. It would also be very unlikely that the tank was fired upon at 1.5km distance with a 10° tilt. Additionally, it is very unlikely that the firing was conducted at close range with reduced charges because the soviets had little data on terminal velocity of german charges and would need to conduct extensive ballistic tests with german charges beforehand.

    A source of uncertainity lies in the fact that the type of AP projectile is not specified. Initial AP for KWK36 was FLAK ammunition: 88mm Pzgr. Gg as of 9.5kg weight (V0:820m/s). Only later, into mid 1943, this was replaced by 88mm Pzgr 39 as of 10.2kg weight (V0: 773m/s). Because the TIGER studied was captured in jan. 1943, it is not likely that Pzgr39 was available for trials. The officially rated, reliable penetration at 1.5km @ 30° for 8.8cm KWK36 was 85mm for the 88mm Pzgr Gg and (91mm for the updated 88mm Pzgr39).

    This trial sheds some light on relative resistence of soviet RHA vs german RHA when fired upon by german projectiles. Caution should be used because it is only one tank, which may have had defective quality.

    Complete penetration of the 105mm front (75mm+30mm laminated, makes for ~97mm single plate aequivalence) would be extremely improbable at 1.5km for the 88mm Pzgr Gg, if the armor would have been of anywhere near the resistence quality of german RHA. 92mm german RHA were required to reliably stop the 88mm Pzgr Gg (no hole through in five out of five consecutive attempts)but the same projectile experienced little difficulties to penetrate the aequivalent of 97mm soviet armor. Note that no attempt was made to determine the maximum range at which penetration does occur. While we now know that the armor below the minimum service acceptance specifications required from german armor plate, we still don´t know how bad it really was. The firing testifies >5% below the resistence at which german plate would be rejected.

    ReplyDelete
    Replies
    1. Here we can see a critical massive Nazi fanatic Troll trying to look like an expert.
      Starting part of the post makes clear he doesn't trust the test. In the medium part he uses this "untrustfull" information to reach a conclussion "This trial sheds some light on resistence of soviet RHA vs german RHA..." but in the next sentence he says this is not a reliable source of information due to two reasons. But at the end he takes this as correct information (again) to reach another coclussion.
      A fanatic is a person who you can never take him as an information source, even a bad one.

      Delete
  2. Notice that the 2nd column of angle´s termed "Impact angle" should be translated as "target angle" instead because the used terminology is misleading.
    Impact angle is associated with a netto compound impact angle , which this line clearly does not give (compare glancing hit #1 with photo #5) but the horizontal deviation angle between target and line of fire (again phot #5, first impact on glacis and subsequent impact on drivers plate shows this deviation from perfect central alignment).

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  3. The Soviets had data on heavy German AA guns since before the war, but sure, just as always you know more about the test than the testers themselves.

    ReplyDelete
  4. It´s not enough to know "data". It´s necessary to know the RP temperature, density and velocity relationship of the charges, information of which remained classified. It would not be handed out to Army personal because only the depot and prooving ground personal had any need for this information, This information cannot be easily deduced even from official rangetables.
    And for the record, the soviets didn´t even got their own official wartime rangetables corrected until a couple of years after end of hostilities.

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  5. Ah yes, the great critical mass knows more about Soviet weapons than the Red Army! Is there any limit to your genius?

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  6. Also it's hilarious how you claim that maximum range of penetration wasn't determined when two of the AP hits didn't penetrate. But I'm sure you're going to post another torrent of lunacy about how it doesn't count because of superior Teutonic craftsmanship or whatever.

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  7. Incorrect. All fair hits penetrated.

    hit #1 was not a fair hit but a ricochet. It had no chance to penetrate due to extreme oblique glancing hit first on the glacis (approx. 66.6° netto compound angle). Subsequently, it didn´t penetrate the drivers plate completely because it already depleted a good deal of energy by the previous the ricochet and plastic deformation of the scoop -as could be expected.

    hit#3 completely penetrated but didn´t hit squarely the plate, thus entered & exited at the same place. This was aided by the location of the hit on the edge of armor. Due to edge effects, this wouldn´t be counted as a fair hit by anyone.

    hit#2 & hit#4 were fair hits. And both penetrated completely.

    hit#5 was HE.

    ReplyDelete
    Replies
    1. Right, hit #3 completely penetrated in the sense that it didn't penetrate at all. Interesting definitions you're using, comrade.

      You might also wish to pay attention to the shell hitting in close proximity to the welding seam without the seam bursting, like it does on German vehicles. But sure, keep cheering on that German supremacy.

      Delete
  8. CAMD RF 38-11355-1545
    That link had Table 4 on it as well. Why not include it?

    ReplyDelete
    Replies
    1. Table 4 describes the effects of the 85 mm gun, which I put in a separate article that was posted earlier: http://tankarchives.blogspot.ca/2017/10/85-mm-vs-soviet-tanks.html

      Delete
  9. Any comments on how a gun with penetration estimated by soviets as only 78mm/30° http://www.tankarchives.ca/2013/03/penetration.html
    was able to defeat a target of 75+30mm@compound angle of 30°+20°?

    ReplyDelete
    Replies
    1. Where do you see a compound angle of 30+20 degrees? The angle in the trials is 20 degrees. It's not impossible to defeat thicker armour at a shallower angle, especially considering the high probability of success required for the table you linked.

      Delete