Analysis of Variance of Firing Angles and Hit Percentages on the Battlefield

Here we solicit numbers from members concerning anything regarding historical numbers that affect a Civil War simulation: hit rates, rates of fire, casualty rates, movement rates, you name it. The idea is that we're really trying to get the numbers for the game right.

Jim
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Re: Analysis of Variance of Firing Angles and Hit Percentages on the Battlefield

Post by Jim »

For some additional information: CW Ballistics blog entry

-Jim
"My God, if we've not got a cool brain and a big one too, to manage this affair, the nation is ruined forever." Unknown private, 14th Vermont, 2 July 1863
born2see
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Re: Analysis of Variance of Firing Angles and Hit Percentages on the Battlefield

Post by born2see »

This is the equation that Norb uses:


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:P


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Last edited by born2see on Tue Oct 16, 2012 3:12 am, edited 1 time in total.
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Marching Thru Georgia
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Re: Analysis of Variance of Firing Angles and Hit Percentages on the Battlefield

Post by Marching Thru Georgia »

So Norb is only doing a 0th order calculation. Sloppy. :laugh:
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Bloody 8th
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Re: Analysis of Variance of Firing Angles and Hit Percentages on the Battlefield

Post by Bloody 8th »

what is the purpose of getting this detailed. I love that you guys are this detailed but couldn't you just put at 150yds so many guys will get hit and so on... Don't kill me on this caus I am very appreciative of your attention to detail and that is what makes this game the best game ever.
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Re: Analysis of Variance of Firing Angles and Hit Percentages on the Battlefield

Post by Willard »

If these numbers are correct why were they always told to low? Doesn't the bullet fall enough already.
The answer is very simple and has nothing to do with mathmatics and everything to do with human nature. Inexperienced shooters have a tendancy to shoot too high and basic marksmanship was something not worked on often enough in the ACW. More time was spent on drill and march than actually shooting rounds down range. To overcompensate with green troops, the command was to fire low minimize the problem.
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Re: Analysis of Variance of Firing Angles and Hit Percentages on the Battlefield

Post by Garnier »

This is the equation that Norb uses:
Obviously the game doesn't calculate ballistics, because if it did, shots would be able to fly past the target and hit someone 500 meters away.

Better to keep it simple and just have a factor for different ranges. But we would love to know what that factor is, since it seems to have an extremely small effect. Troops firing at 200 yards kill almost as many as at 20 yards.
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Hancock the Superb
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Re: Analysis of Variance of Firing Angles and Hit Percentages on the Battlefield

Post by Hancock the Superb »

Incorrect again. Your homework for today is to calculate the drop of a bullet traveling 950 ft/sec over the distances of 50, 100 and 150 yd neglecting air friction. Then calculate dTheta from this result. Tomorrow we will add air friction back in. Note, you can save yourself some work by reorienting your frame of reference so you only have to solve for one triangle.
First off, I would appreciate it if you would kindly refrain yourself from belittling my credibility; I understand that you may have significant experience in the area of projectile motion, but that does not give you permission to "teach".

Second, I checked my work with one of my physics professors, and as I expected, my physics were sound; it is perfectly reasonable to omit gravity as long as we assume that each bullet will fall approximately the same distance (which I will proceed to show why this works). Remember, I am trying to estimate the angle of error needed to just hit the target, not find any exact angle. The statistical analysis can be compared to that of an Analysis of Variance Test (ANOVA).

Since each of the three hypothetical bullets will travel roughly the same distance; at 10 yards the distances are different by 4 orders of magnitude, which will not influence my work with 3 significant figures. Thus, since the distances, velocities and times can be considered the same, gravity will affect each bullet the same (in terms of vertical displacement). Taking advantage of the accelerating reference frame of the bullet, each bullet can be assumed to travel in a straight line. Remember, I am not trying to find specific angles. The amount I add due to gravity to the lowest angle, I would have to add to the upper angle. So when I "subtract" the two angles (I actually bypassed the step using triangles and the law of cosines), the angle difference due to gravity is cancelled out, further indicating that using the accelerating reference frame of the bullet is a reasonable approach, considering I am merely exact to 3 significant figures.

Hopefully this will sway readers as to why my approach can be considered accurate.
Hancock the Superb
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Re: Analysis of Variance of Firing Angles and Hit Percentages on the Battlefield

Post by Hancock the Superb »

This is the equation that Norb uses:
Obviously the game doesn't calculate ballistics, because if it did, shots would be able to fly past the target and hit someone 500 meters away.

Better to keep it simple and just have a factor for different ranges. But we would love to know what that factor is, since it seems to have an extremely small effect. Troops firing at 200 yards kill almost as many as at 20 yards.
This is what I am hoping to get at: the game models ballistics in a fashion that is potentially inconsistent with reality. Hopefully we will gain access to these factors.
Hancock the Superb
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Re: Analysis of Variance of Firing Angles and Hit Percentages on the Battlefield

Post by Marching Thru Georgia »

Hancock The Superb wrote:
First off, I would appreciate it if you would kindly refrain yourself from belittling my credibility; I understand that you may have significant experience in the area of projectile motion, but that does not give you permission to "teach".

Second, I checked my work with one of my physics professors, and as I expected, my physics were sound; it is perfectly reasonable to omit gravity as long as we assume that each bullet will fall approximately the same distance (which I will proceed to show why this works). Remember, I am trying to estimate the angle of error needed to just hit the target, not find any exact angle. The statistical analysis can be compared to that of an Analysis of Variance Test (ANOVA).

Since each of the three hypothetical bullets will travel roughly the same distance; at 10 yards the distances are different by 4 orders of magnitude, which will not influence my work with 3 significant figures. Thus, since the distances, velocities and times can be considered the same, gravity will affect each bullet the same (in terms of vertical displacement). Taking advantage of the accelerating reference frame of the bullet, each bullet can be assumed to travel in a straight line. Remember, I am not trying to find specific angles. The amount I add due to gravity to the lowest angle, I would have to add to the upper angle. So when I "subtract" the two angles (I actually bypassed the step using triangles and the law of cosines), the angle difference due to gravity is cancelled out, further indicating that using the accelerating reference frame of the bullet is a reasonable approach, considering I am merely exact to 3 significant figures.

Hopefully this will sway readers as to why my approach can be considered accurate.
As an actual physicist, I can tell you that what you have been writing is shear nonsense. Gravity does not act linearly as you are trying to assume, but as the square of the time the projectile has been in flight. It cannot be omitted. Until you grasp this fact, you are simply digging the hole you are in deeper. I must say that trying to invoke general relativity, incorrectly, was original but nonetheless wrong.

If you want to make arguments as to why very few people were hit at distances of 100 yd. or more while in battle using qualitative arguments such as smoke, lack of training, nerves, etc. that's fine. Historians do those sort of things all the time. But when you make quantitative calculations, you need to know what you are doing. No one can check what effect smoke had on accuracy 150 years ago. But someone can always check your arithmetic.
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Hancock the Superb
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Re: Analysis of Variance of Firing Angles and Hit Percentages on the Battlefield

Post by Hancock the Superb »

As an actual physicist, I can tell you that what you have been writing is shear nonsense. Gravity does not act linearly as you are trying to assume, but as the square of the time the projectile has been in flight. It cannot be omitted. Until you grasp this fact, you are simply digging the hole you are in deeper. I must say that trying to invoke general relativity, incorrectly, was original but nonetheless wrong.
As I have evidently been unable to communicate: I have abandoned gravity all together. The downward trend of the bullet in the screen is from firing at below a horizontal angle. The effect of gravity is not accounted for because as I showed in the previous post, the time it takes for each of the three bullets to hit the target is the same to three significant figures, thus the effect of gravity (verticle displacement) is the same on each bullet to three significant figures. So when I find the difference of the angles, the angle added due to gravity (as the projectile takes an parabola instead of a line) is cancelled on both sides of the equation.

The accelerating reference frame is merely another justification as to why each bullet travels in a straight line in relation to the other bullets. I may be wrong in invoking this justification, but in terms of what I have learned, it is used correctly as long as it is to only evaluate the displacement of the other bullets.

Look, I am not doubting that you are correct: gravity plays an important role in finding the angle of error. I am trying to explain why my way of calculating the angle accounts for gravity in a different fashion than yours.

You are extremely well qualified as a working physicist; however, my physics professor is just as qualified and believes my model accurately captures the angle of error that my study is focused on.

1/2at^2 = 1/2at^2 regardless of initial velocities as long as the times are the same. Total displacement = v0t + 1/2at^2. I am subtracting the 1/2at^2 from each equation because it affects the displacement the same. So for a downward fired bullet, dx<0. For a horizontal bullet, dx=0. For a upward fired bullet, dx>0. In my several years of experience in the realms of physics and calculus, the equations used and the math applied are correct. If anyone has different equations and demonstrates a different answer than mine, I am an avid learner. I am the first to say that bullheadedness hinders learning.
Last edited by Hancock the Superb on Wed Oct 17, 2012 7:56 am, edited 1 time in total.
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