Mobius' Dispatches from the Front

August 8, 2017
It looks like there was no merit to the British data on the dispersion of the KwK 42 shell. Miles Krogfus came through with the actual firing table for the gun. H. Dv. 119/325 link

July 24, 2017
The idea of having a two tier ranging error based on the sight range is a no go.  Sight pictures for sights where the text says they only go to 1500m or some small distance shows they are calibrated beyond 2000 and many cases
3000m.  The text on the Russian SU-152 sight, ST-10 says it's range is 900m and the ST-18 is up to 1500m.  The sight itself reveals that it is calibrated to over 5000m.  This is optimistic to say the least.  So I guess I'm back to a single standard deviation for a sight.   Now this assumes the sight pictures found on World of Tanks or War Thunder are accurate.  The text descriptions of the sights on these two telescopic sights say that they have limited range but the periscope sight goes to 5000 meters.  Maybe the game makers melded the two sights into one for game play.

July 17, 2017
Page 32 has a picture of the updated menu for the Ballistics program.   The range estimation error is now a product of the guns sight of the weapon.  The base factor starts off as Field of View times magnification x ratio of calibration range.  Then other subjective factors like milli-radian, glass clarity or range and lead marks ease of use.  This yielded a single factor.   But, I was thinking that it might be two factors.  One would be a ranging error up to the limit of its range calibration then thereafter there would be a higher ranging error as the gunner would have to estimate the range even more.  This would result in a step in the to hit curve where the first ranging error ends and the second begins and continues. 
Then there's the problem that if they have say a range error do they know when they are beyond the range marks of their sights?
This may be over thinking something that is more in the realm of crew quality and not tank attribute.


June 14, 2017
Working on updating Naab naval ballistics program.   It is based on an old version of Nathan Okun's facehard basic program.   Looks like a lot of detail shell factors have changed.  I haven't checked other aspects of the program yet.

May 18, 2017
One question over at the Axis History forum was about the deviation of the 75mm/L70 KwK 42 gun. I had thought it was like the 75mm/L46 KwK 40 gun but more accurate. Looking into this more I found some text I saved from what it seemed to be a British report of the gun at 2187 yds.
German extreme dispersion 2000m
1.75 w x 1.5h 2187yd
75mm/L70 69" / 59"
Using this ratio and solving for German training and action values with dispersion only I found that I could resolve the values.
So this is the result:
...............................my calculations……….................table
Range…......w /h……........Training/Action.……......Training/Action
1000m___0.338/0.29______=100/96.8__________>100%/97%
1500m___0.563/0.484____ =98.6/72.4_________ >100%/72%

2000m___0.79/0.68______ =92.1/48.5__________>92%/49%
2500m___1.114/0.955_____=73.3/28.6__________>73%/29%
3000m___1.44/1.23_______=55.1/18.4__________>55%/18%

What is surprising is that it works. The ratio is the same all the way to 3000 meters.
A few things were discovered solving this.
1. Lateral dispersion is greater than vertical dispersion. The 128mm PaK 44 also has greater lateral dispersion than the vertical dispersion. Most German guns have the vertical deviation greater than horizontal deviation.
2. 'Extreme' dispersion apparently means 90% zone as opposed to the German 50% zone.
3. The 90% zone is 2.44 times the 50% zone. If yards are converted to meters this seems to work.
2.44 x 0.79m x 0.9144 = 1.76 ~ 1.75 yd.
Actually back in time someone made a math error. To convert meters to yards, meters have to be divided by .9144 not multiplied by that amount.


April 12, 2017
Well,

Gonzanga wasn't the winner, but they were in the finals and came in second. Villanova was upset early and didn't finish in the final 8.   I don't know if I'm going to change the program.  I could add a conference factor that might weigh the teams in a conference more or less.  I probably won't work on this until next season. 


March 15, 2017
Someone might ask why am I wasting my time with this March Madness Basketball stuff on a wargaming site. It's just an exercise in probability.   I'm using the Ballistic hit rectangular probability equations for something they weren't designed for. 
So the most probable tournament winner is Gonzanga.  Next is Villanova. So if these don't show up in the final four I might change the probability equations to the ellipse probability equations as they have less certainty above 50%.  So teams with lower rankings and worse records have a little better chance.

Also I'm working on a new program to feed sighting range estimation into the Ballistics program.   Up to now it has just been a guess of how good the range estimation a tank gun with a certain sight could achieve.  I'm trying to make a quantitative estimate based of telescope sight characteristics.  Like magnification x field of view x light transmission % as a factor.   Then this adjusted by training and ranging calibration and maybe something else.   It will produce a standard deviation of range error.  I'll post a page with different sight values when I am finished..

March 13, 2017
It is back!   March Madness Basketball Bracket Breaker program has been updated for the 2017 March Mad Basketball tournament. After a hiatus of 3 years I decided to play again.
Download

January 17, 2017
I had to revise my Soviet gun dispersion page 34 when I found out that the 1951 US document I was basing my calculations on had mis-translated captured Russian firing table information.  It had translated Russian 'mean deviation' for 'median deviation'.   That may seem a small matter but they are not mathematically the same.   When the deviation is described as 'median deviation' it results in making the 50% probability of a hit ~18% less likely.   In effect making Russian guns less accurate.   Several pages have to be changed so it may take awhile to do.

December 22, 2016
A new page of a tongue-
in-cheek look at R&D military science in Star Wars.

October 14, 2016
A new page on some strange ballistic behavior  I found examining WWII Firing Tables.  I have no opinion as to