I sight my guns in 3" high at 100 yards. For most calibers, that keeps the bullet from usually no more than 6" high at it's highest point around 200 yards, and will be back down to 0, or where it started at the muzzle height, anywhere bewteen 250-300 yards. Some heavy, slow calibers and flat, fast calibers can shorten or stretch the distance a little more.
Does that make sense? If not, I can try to explain a little more.