A Sniper is required to accurately determine distance, to properly adjust elevation on the sniper weapon system, And to prepare topographical sketches or range cards. Because of this, the Sniper has to be skilled in various range estimation techniques.
a) Nature of the target
1) An object of regular outline, such as a house, appears closer than one of irregular outline, such as a clump of trees.
2) A target that contrasts with its background appears to be closer than it actually is.
3) A partly exposed target appears more distant than it actually is.
b) Light conditions
1) The more clearly a target can be seen, the closer it appears.
2) When the sun is behind the observer, the target appears to be closer.
3) When the sun is behind the target, the target is more difficult to see and appears to be farther away.
c) Nature of terrain
1) As the observer's eye follows the contour of the terrain, he tends to overestimate distant targets.
2) Observing over smooth terrain, such as water, sand, or snow, causes the observer to underestimate distant targets.
3) Looking downhill, the target appears farther away. Therefore looking uphill makes the target appear closer.
Range estimation formula
width or height ( in inches ) x 25.4 divided by number of the mils of the target as seen in the M3A = range