Target Elevation

[rexford]

An earlier post asked it target elevation could increase accuracy. Elevation of the aim center relative to gun barrel was tested using following scenario:

Target is a fully exposed M4A1 Sherman. Aim point is center of mass (firer tries to drop round on middle of observed tank mass).

Panther and M4A1 Sherman (75) try to hit the target on the center of mass, with average range estimation error of 25% distributed statistically (bell shaped distribution curve varying from 0% error to 75% error).

The higher a target is relative to the gun barrel, the higher the hit %:

Target M4A1 at 500m

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Panther Accuracy at 500m

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Aim point is +2.1' higher than barrel, 99.5%

aim point elevation equal to barrel, 97%

aim point -2.1' lower than barrel, 91%

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Sherman 75 accuracy at 500m

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aim point +2.1' above barrel, 83%

aim point same elevation as barrel, 74%

aim point -2.1' below barrel, 67%

Conclusions

Target elevation matters alot at 500m.

When target aim point is below level barrel, trajectory is aimed downward and gravity greatly curves trajectory, lowering accuracy. When shot is aimed at higher target, trajectory is flatter around target range and range estimation errors aren't as critical.

Slow rounds are impacted more than faster, flatter trajectories due to greater curvature of Sherman 75 flight path.

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M4A1 target at 1000m

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Panther accuracy

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33% with target aim point +2.1' above barrel

30% when target at same elevation as barrel

29% when target aim point -2.1' below barrel

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Sherman 75 accuracy

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21% when target aim point +2.1% above barrel

21% when aim point equal elevation to barrel

20% when aim point -2.1' below barrel

This shows that the simplified trajectory equation may not be totally satisfactory for low to medium velocity rounds fired at medium to close range, since simple equation assumes barrel at same elevation as target aim point.

Above analysis also suggests that shooting at small targets introduces two problems, smaller profile causes misses with higher % of range estimates, and lowered accuracy when trajectory has to be aimed downward. And that vehicles such as Hetzer and StuG III, and anti-tank guns (especially dug-in guns), might have better accuracy than a 76mm Sherman due to lower barrel elevation.

At 1000m and beyond, barrel elevation relative to target center of mass is not as critical for elevation differences studied, based on above results.

Panther accuracy at 500m seems higher than in CM, regardless of target aim point.