Dispersion data for KwK 42 L/70

[Peasant]

Why are there always less than the ten prescribed shots in the 122mm (7-9 actual) samples? this obstructs the comparability...

Welcome to the soviet Russia. Unlike in the countries with an uninterrupted legacy of military R&D, the soviet specialists had to re-invent many things from scratch, including the optimal ballistic testing methodology.
Still, this shouldnt' constitute a major problem, is it? One can still use these results to estimate an average and a standard deviation for each gun, if I'm not mistaken.

[critical mass]

This raises the question of how can we guard against the possibility that there were other shots, which are thrown out because they were recorded as outliers? You´d expect one outlier in 20, not one to three in 10...
It´s not a trivial issue when we pursue for comparative data.
If alternatively one assumes that the KWK43 /PAK 43 was tested in groups of ten shots and the 122mm was tested in changing groups of 7-9 shots one would nevertheless still need to normalize against the different sample size before extracting standart deviations. I infer that this would change the results somewhwat.

F.e. the U.S.N. differenciated between appearent dispersion and true dispersion. For the latter, the average dispersion was related to the number of shots in each group using the simple formula SQRT (n/n-1), where for a given number of shots n the true mean dispersion results from the multipliers given below:

n2 = 1.414
n3 = 1.225
n4 = 1.155
n5= 1.118
n6= 1.095
n7= 1.080
n8= 1.069
n9= 1.061
n10=1.054
n11= 1.049
n12= 1.044
(...)
n20= 1.026
(...)

[critical mass]

So if I crank the numbers in,

the first example on 2000m (n=8) range yields these results:
apparent mean dispersion: 0.50 m horizontal and 0.346 m vertical
true mean dispersion: 0.535m horizontal and 0.37 m vertical
resulting 50% zone: 0.90 m horizontal and 0.625 m vertical

2nd example on 1000m (n=7) yields:
apparent mean dispersion: 0.20 m horizontal and 0.18 m vertical
true mean dispersion: 0.22m horizontal and 0.19 m vertical
resulting 50% zone: 0.37 m horizontal and 0.33 m vertical

(...and so on...)

notice the probable error is excactly half the 50% zone, and the total pattern is approx. four times the 50% zone.

[Peasant]

Excellent overview of this topic by Ian Holloway here: https://qr.ae/prwfyl

[Yoozername]

Excellent overview of this topic by Ian Holloway here: https://qr.ae/prwfyl

It is. A missing component is IF the weapon is zeroed. German reports with long barreled guns note this especially. Even Pak 43, that have been zeroed, and locked, after a road march will lose that calibration. Movies that show tanks running through buildings are funny.

An attacking force is at a distinct disadvantage to a defending force that has set up range cards.

[Peasant]

It is. A missing component is IF the weapon is zeroed. German reports with long barreled guns note this especially. Even Pak 43, that have been zeroed, and locked, after a road march will lose that calibration. Movies that show tanks running through buildings are funny.

An attacking force is at a distinct disadvantage to a defending force that has set up range cards.

Good call, I haven't considered this factor. Have you seen any studies done to quantify this effect?

[Yoozername]

Yes. Quite a few at panzer-Elmito.com Spaniard translates many German reports into Spanish, which can be translated to English. The Germans produced ammunition that was used to zero the weapons. Basically it had weight and shape matching real AP ammunition. It did not, of course, have the alloys and heat treatments, etc. Tankers I have talked to mention BOT (Burst On Target) as a field remedy in combat. Basically you aim normally, watch where the tracer goes, any gross mismatch means quickly adjust the optics to match that spot. Rinse and Repeat. Not optimal, but you do want to fight and survive.

[Yoozername]

Another issue is 'Can you even spot the tracer?' This is an issue with certain designs of optics, muzzle brakes, ground conditions, commander buttoned up, etc. Basically, the whole process is a closed loop affair depending on feedback. Otherwise, you are just bombarding and trusting luck and quantity.

The Germans, after they captured T34s and Soviet crews, were surprised that they did not seem to zero the weapons. After zeroing the T34 76mm L41 gun, the Germans considered it, to be not only deadly, but an accurate piece. I shoot maybe a few times a year at most. and I am amazed at people firing one shot and adjusting the sights. Statistical common sense means 3 rounds are the minimum sample that can be of value. I usually move away from them at the range.

[Corgood]

Deleted

[Corgood]

The soviets have tested the accuracy of Kwk 43 gun on Tiger II. If we compare the R-50 and R-100 values and the distances from the aim point with those of the D-25T gun posted previously, we see that the german gun is generally more accurate, although the difference is less than one might expect.

Can i get this pictures original docs?

[Peasant]

The soviets have tested the accuracy of Kwk 43 gun on Tiger II. If we compare the R-50 and R-100 values and the distances from the aim point with those of the D-25T gun posted previously, we see that the german gun is generally more accurate, although the difference is less than one might expect.

Can i get this pictures original docs?

Sure: https://mega.nz/file/WWQwQYZJ#hhcke5aWh ... eBuxjoOX3M

[Corgood]

Thx