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RE: High Velocity AP round hit-zones

Posted: Mon Dec 03, 2012 7:32 pm
by Mobius
This curve too is sinusoidal. I ran a 30% error as if it were the std. dev.
Also, changed the gun firing height to 4'.
The curve is from the data.


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RE: High Velocity AP round hit-zones

Posted: Mon Dec 03, 2012 8:24 pm
by Mobius
This what a sinusoidal accuracy curve looks like.

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RE: High Velocity AP round hit-zones

Posted: Mon Dec 03, 2012 9:22 pm
by Yoozername
I assume you have a standard target height/width? 2.5m x 2m?

Also, the 'Over(m)', I take this is vertical dispersion at the actual range?

RE: High Velocity AP round hit-zones

Posted: Mon Dec 03, 2012 10:29 pm
by Yoozername

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[/quote]

Can you run this with the following numbers:

Range: 183, 229, 274= Aim 250
Range: 320.......640= Aim 500
Range: 686.......869= Aim 775

RE: High Velocity AP round hit-zones

Posted: Tue Dec 04, 2012 12:19 am
by Mobius
I can't give it a fixed aim number. It goes by fixed range error. So I have to give it a different range error for each row.


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RE: High Velocity AP round hit-zones

Posted: Tue Dec 04, 2012 1:19 am
by Yoozername
I suppose you could just change the numbers a little. That is, just enter:

183 249
229 250
274 251
320 252

366 496
411 497
457 498
503 499
549 500
594 501
640 502

686 774
732 775
777 776
823 777
869 778

Edit: Can you just enter the minimum range error??? My whole point is that it should not matter. I am not sure if you are following this.


RE: High Velocity AP round hit-zones

Posted: Tue Dec 04, 2012 2:30 am
by Mobius
When the range and the aim point are only a few meters apart it reduces down to just the dispersion inaccuracy.

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RE: High Velocity AP round hit-zones

Posted: Tue Dec 04, 2012 2:42 am
by Yoozername
What happens if you inpt these numbers?
ORIGINAL: Yoozername

I suppose you could just change the numbers a little. That is, just enter:

183 249
229 250
274 251
320 252

366 496
411 497
457 498
503 499
549 500
594 501
640 502

686 774
732 775
777 776
823 777
869 778

Edit: Can you just enter the minimum range error??? My whole point is that it should not matter. I am not sure if you are following this.


RE: High Velocity AP round hit-zones

Posted: Tue Dec 04, 2012 10:02 am
by Mobius
Right now it only computes if the aim is greater or equal to the range. In a short aim when the projectile hits the ground the run is over. To work with the formula it would have to be made to continue on and pass beneath the target to find the distance from the path to the center of the target.

Here are a subset of what I can find.

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RE: High Velocity AP round hit-zones

Posted: Tue Dec 04, 2012 12:34 pm
by Mobius
I can find precious few live fire accuracy tests. All I do find are British. Though the two don’t agree with each other. This table has an unknown target size. Assuming it is Panzer IV sized I ran another test with different gun heights and 25% ranging error. 17-pdr and 75mm match to a high degree. The 6-pdr doesn’t match the WO 291/180. And the APDS values seem highly optimistic.

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RE: High Velocity AP round hit-zones

Posted: Tue Dec 04, 2012 1:19 pm
by Yoozername
I think I have some 17 pdr. info also.

How about entering 425 aim up to 411 range, enter 650 aim up till 640 range and 875 up to 869 range? That should work even though it isn't exactly the zone fire I would want. It could demonstrate some principles.

RE: High Velocity AP round hit-zones

Posted: Tue Dec 04, 2012 11:41 pm
by Mobius
411-425=100%
640-650=89.8%
869-875=76.7%

RE: High Velocity AP round hit-zones

Posted: Wed Dec 05, 2012 12:24 pm
by Mobius
Here an interesting report on range estimation.
http://www.dtic.mil/dtic/tr/fulltext/u2/a132616.pdf

RE: High Velocity AP round hit-zones

Posted: Wed Dec 05, 2012 2:26 pm
by Yoozername
ORIGINAL: Mobius

When the range and the aim point are only a few meters apart it reduces down to just the dispersion inaccuracy.

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So, if I understand this correctly, you are saying that this is for a German 7,5cmL48 gun firing APCBC or APCR?

This data shows a weapon with no range error? Target size 2.5m by 2m?

Just for reference:

75L48 TUNGSTEN CORE
100m....0.1m/0.0m
300m....0.2m/0.1m
500m....0.3m/0.3m
800m....0.5m/0.4m
1000m..0.7m/0.6m

75L48 APCBC
100m....0.1m/0.0m
300m....0.2m/0.2m
500m....0.3m/0.2m
800m....0.4m/0.4m
1000m..0.6m/0.5m


RE: High Velocity AP round hit-zones

Posted: Wed Dec 05, 2012 5:05 pm
by Mobius
ORIGINAL: Yoozername
So, if I understand this correctly, you are saying that this is for a German 7,5cmL48 gun firing APCBC or APCR?
APCR
ORIGINAL: Yoozername
This data shows a weapon with no range error? Target size 2.5m by 2m?

Just for reference:

75L48 TUNGSTEN CORE
100m....0.1m/0.0m
300m....0.2m/0.1m
500m....0.3m/0.3m
800m....0.5m/0.4m
1000m..0.7m/0.6m

75L48 APCBC
100m....0.1m/0.0m
300m....0.2m/0.2m
500m....0.3m/0.2m
800m....0.4m/0.4m
1000m..0.6m/0.5m
It doesn't matter the target size or range error, it's a gun variable.


RE: High Velocity AP round hit-zones

Posted: Wed Dec 05, 2012 8:59 pm
by Yoozername
So, I assume that P(Hit) is a percentage to hit something? Does that something have any size characteristics? Or it could be a KV-2 or a lend lease jeep?

RE: High Velocity AP round hit-zones

Posted: Wed Dec 05, 2012 11:40 pm
by Mobius
For the German projectiles it is the size of a T-34/76 from the front. I take a cue from the WO tests and use the most common size of the enemy tank.

RE: High Velocity AP round hit-zones

Posted: Thu Dec 06, 2012 3:39 pm
by Yoozername
At 800 meters, you have about 1 out of 5 APCR shots missing the target T34 (I assume this is first round accuracy on a known range). The vertical 50% dispersion is 0.5 meters at 800 meters. Even if I use 3 sigma conversion, it is just barely over the target height. About 2.28m. The 0.14 meter distance, both over and under the target, represents, what...a 4-5%?


RE: High Velocity AP round hit-zones

Posted: Thu Dec 06, 2012 4:44 pm
by Mobius
It is the first shot 30% range error. Firing at 1040m will be 1.65m above the center of the target at 800m.

RE: High Velocity AP round hit-zones

Posted: Thu Dec 06, 2012 4:47 pm
by Yoozername
This is the data I am referring to.
ORIGINAL: Mobius

When the range and the aim point are only a few meters apart it reduces down to just the dispersion inaccuracy.

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