German OOB 16: minor corrections

[Pibwl]

Nicer photo for 080 Opel is 20016 (Hungarian one)

[sabresandy]

Orbat 16 weapon 10, the sPzB41/61, is modeled with a high HEK value consistent with autocannon. This is the squeezebore 28mm light cannon. The problem is, all sources I can find indicate that it was single-shot, not automatic, and thus its HE value should be very low, consistent with other small-caliber single-shot cannon. Are there any sources that indicate it was automatic?

[DRG]

now 1

[PvtJoker]

Originally Posted by sabresandy

Orbat 16 weapon 10, the sPzB41/61, is modeled with a high HEK value consistent with autocannon.

The AP/Sabot penetration of this weapon is also quite generous at 10. Hogg gives 94mm at 100 meters, which is the best number I could find for this gun, but since the penetration does not drop from 10 at 100 meters in the game with the current range (25 hexes), it is still excessive. A. Ivanov gives 75mm at 0 degrees @ 100 meters. Chamberlain, Doyle & Jentz have even lower numbers; 60mm at 30 degrees at 100 meters. 0 meters penetration extrapolated from their numbers would be only 61mm at 30 degrees, which would suggest only about 80mm at 0 meters & degress (i.e. the same as Ivanov).

Even if we go by Hogg's numbers (Gander & Chamberlain have the same with more data points), 10 is too much because of the way the game handles the close range penetration. The closest to Gander & Chamberlain ("Small Arms, Artillery and Special Weapons of the Third Reich") numbers would be achieved by Penetration 9 and range 30. It would also take into account the lower figures given by other sources mentioned above, in other words at some ranges penetration is 1 lower than Gander & Chamberlain give, but also meet at several points.

[DRG]

It looks like Wiki is using Ivanov's numbers. 8 seems more likely but this info has me questioning the sabot range given in the game. It would appear in game terms the weapon range should be 20 not 25 and the sabot range 10

[PvtJoker]

Originally Posted by DRG

It looks like Wiki is using Ivanov's numbers. 8 seems more likely but this info has me questioning the sabot range given in the game. It would appear in game terms the weapon range should be 20 not 25 and the sabot range 10

It's a squeeze bore weapon with only APCNR available as anti-tank ammunition. I don't know what kind of sights the gun had, but extrapolated from Gander & Chamberlain data it should be able to penetrate about 10mm still at 1500 meters (49mm even at 800 meters, which is their last data point; I extrapolated linearly from 600, 700 and 800 meter numbers). APCNR projos had quite good external ballistics due to high sectional density and relatively low drag (unlike APCR/HVAP) and were similar to post-WW2 APDS projectiles in that regard.

These are the Gander & Chamberlain numbers; first column is range in meters, second is penetration at 0 degrees and third column at 30 degrees:

100 94 69
200 86 65
300 79 60
400 72 56
500 66 52
600 60 48
700 54 44
800 49 41

I don't know where Wiki gets their "effective range". It might be the historically preferred engagement range, which however is not at all the same thing as effective range. In general the whole concept is rather poorly defined; for example AT rifles typically had an "effective range" of about 500-600 meters against their primary targets (= tanks), but they were useful against light armor (armored cars and APCs) and unarmored vehicles at much longer ranges.

For example the Boys ATR had sights to 500 meters only (300m in later versions), but the gunners compensated by aiming at the top of the target instead of center if they had to shoot at longer ranges. The flat trajectory (i.e. low drop) of the bullet made that quite effective when shooting vehicle-sized targets (target height 1.5 meters or more). Many other ATRs even had sights to 1000-1500 meters just for plinking light armor and unarmored targets, even though fire against tanks was usually opened no further than at 300 meters and often much closer.

[DRG]

I do love the way things like this take on a life of their own and spin off in unpredictable ways.

Looking at the production dates and what we have in the game I have to question these three units....

166 - SdKfz 250/11 - uClass 032 : slot 1 - Available 01/043 to 12/046
218 - SdKfz 251/10a - uClass 125 : slot 1 - Available 01/043 to 12/046
832 - SdKfz 221/2 - uClass 240 : slot 1 - Available 07/043 to 12/046

they must have been very very rare past the beginning of 1944 which means one or two of those units might be deleted but that should give some of you something to investigate for me and the first thing would be when the SdKfz 250/11 with the 2.8 was in service.

Also, I will be revising some ammo numbers based on Culver and Feist's info. The number of rounds for the 37mm and 28mm versions is far too low in the game and the revision will make them far more potent


OK,----- reading the text of the book says that mounting the PzB41 was a "common" modification early in the war on a stock SdKfz 250/1 simply by replacing the Mg34 mount at the front of the fighting compartment and it goes on to say that the PzB41 was phased out of service because of the Tungsten shortage but "Isolated examples lasted long enough to be mounted in the 251/1 Ausf D which appeared in the fall of 1943."



Don

[Pibwl]

On the other hand, in spite of small caliber, it used HE shells (relatively long - http://odkrywca.pl/forum_pics/picsforum6/p064.jpg), so maybe it should be more than HEK 1.

According to Russian Natzvaladze (although probably basing upon some other source), ROF was 12-15 RPM, so it was quite big for a single-shot weapon. Also he gives penetration "at the attack angle of 60deg.": 60mm at 100 m, 19mm at 1000 m.

[PvtJoker]

Originally Posted by Pibwl

On the other hand, in spite of small caliber, it used HE shells (relatively long - http://odkrywca.pl/forum_pics/picsforum6/p064.jpg), so maybe it should be more than HEK 1.

According to Russian Natzvaladze (although probably basing upon some other source), ROF was 12-15 RPM, so it was quite big for a single-shot weapon. Also he gives penetration "at the attack angle of 60deg.": 60mm at 100 m, 19mm at 1000 m.

Those penetrations numbers are the same as given by Chamberlain, Doyle & Jentz in "Encyclopedia of German Tanks of World War
Two". They also give 40mm at 500 meters (same angle). I did make a stupid error in my earlier extrapolation; correctly extrapolated penetration at muzzle would be 65mm at 30 degrees from those numbers.

In any case, good approximation of the data in game would be either AP Penetration 9 with range 30 if we go by Hogg, Gander & Chamberlain or Penetration 8 with same range if we go by Chamberlain, Doyle & Jentz. Range less than 30 gives too low numbers at 800-1000 meters. If Sabot is used, penetration 8 is clearly better since the Sabot calculations have more randomness at close ranges (by APCALC), but the range should IMHO still be 30.

As for the HE kill; for single shot weapons HE kill is standardized to 1 from 20mm to 39mm. The actual shell had only 5g of PETN explosive, so unless the fragmentation was really optimal, it would not have been very effective, anyways.

[Pibwl]

286 Panzerturm PzV - it is commonly known as Pantherturm - maybe it's a better name?