A ballistics trajectory is a bullet's expected flight path. A number of external forces have an impact on the ballistics trajectory of a bullet.
A downward force called bullet drop expands the trajectory range in a downward arc. The bullet's energy, as created by the force of the hammer and the power provided by the explosion of gunpowder in a bullet, affect the bullet's projected distance. Windage, or friction, and velocity also affect the ballistics trajectory. Windage is created by both the movement of the projectile through the air's resistance which shortens the flight path and by cross-directional wind that redirects the projectile to one side or the other.