This is from Hortons website
Hunting Tip: Arrow Drop

Know your crossbow, it's not a gun. The maximum recommended hunting shot range with your Horton crossbow is 40 yards. As illustrated in the trajectory chart, a modern hunting crossbow sighted in at 20 yards, will impact the arrows 21 inches low at 40 yards. During the off season, practice shooting at unknown yardage, and guessing yardage to your hunting target in the woods. Horton's Dial-A-Range® trajectory compensator and Mult-A-Range® scope can greatly help you reach your accuracy potential. Because of the trajectory associated with crossbows and all other archery associated weapons, it is a good idea to clear out and establish open shooting lanes. Down range obstructions like overhanging tree limbs can spoil the shot of a lifetime!