The Ups Downs of Shooting
By: Steve Galea
Confused as to whether you're supposed to aim higher or lower on a target when shooting up- or downhill?
You will never forget again, if you remember that a projectile is only affected by gravity over the horizontal distance it travels, regardless of the up or down angle of the shot. Consider the diagram.
The slope represents the path of the shot (in this case a downward angle). Meanwhile, the baseline shows the horizontal distance over which gravity acts upon the projectile. Note the horizontal distance is always shorter than the path of the bullet on any upor downhill shot.
What does this mean? Say you’re at the top of a hill about 100 yards in height and you see a deer at its base (by direct line of sight 140 yards distant). Using the Pythagorean theorem (A2 + B2 = C2), you could prove that although the bullet travels 140 yards on the downward angle, the horizontal distance it covers (in which gravity affects it) is approximately 98 yards.
This is a far cry from the 140 yards you perceive the range to be. If you were to hold your rifle so it would be dead on at 140 yards, you’d shoot high, since gravity is only acting on your bullet for 98 yards. Admittedly, this is not a big deal with a relatively flat-shooting rifle like a 30.06. On the other hand, if you were using a .44 Rem. Mag sighted in at 100 yards and held as you would for a 150-yard shot (approximately five inches high), a bad hit or even a miss might result. If you aimed lower, as you would for a 100-yard shot, your only worry would be how to drag your deer out of that gorge.
Bottom line? Aim low when shooting on up or down angles. How low depends on the approximate horizontal distance to your target.