The explanation of the physical situation for uphill/downhill shooting begins with a simple observational fact - that bullet drop at any given range from the muzzle is almost independent of firing elevation angle. So, the bullet path is zero at the zero range, and then becomes negative at distances greater than the zero range. The bullet will arc over and cross the line of sight at the zero range. The bullet path is then positive throughout this portion of the trajectory. Somewhere near the muzzle, the bullet will follow a path that rises and crosses the line of sight, then travel above the line of sight until the target is reached. At the gun’s muzzle, the bullet path is negative because the bullet starts out below the line of sight of the shooter. Thus, it would be where the shooter would “see” the bullet pass at any instant of time while looking through the gun sights, if that were possible. Drop is expressed as a negative number, denoting that the bullet falls away from the extended bore line as the bullet travels.īullet path, on the other hand, is always measured perpendicular to the shooter’s line of sight through the sights on the gun. At any range distance measured along either a level range or a slant range, drop is then the vertical distance between the extended bore line and the point where the bullet passes.

Bullet drop is always measured in a vertical direction regardless of the elevation angle of the trajectory.

One may refer back to Figure 3.0-1 concerning these definitions. Throughout this subsection the terms “bullet drop” and “bullet path” will be used frequently, so we will review the definitions of those terms before we begin to explain the physical situation. In this subsection, we will try to explain the physical situation carefully so that it can be understood clearly, and then provide some examples using Infinity to perform precise calculations. In fact, at the present time some literature has information that is simply erroneous. This effect is well known among shooters, particularly hunters, but how high the gun will shoot is a subject of considerable controversy in the shooting literature.

When a gun is sighted in on a level or nearly level range and then is fired either uphill or downhill, the gun will always shoot high. 3.3 Effects of Shooting Uphill or Downhill

Shooting at incline