In terms of archery, the energy an arrow possesses as a consequence of it's motion is referred to as Kinetic Energy (KE). KE is transferred to the arrow from energy stored in your bow. KE is a factor of weight and speed and is commonly expressed in foot pounds (ft/lbs). For hunting purposes, the energy stored in your bow should be used to maximize the KE potential of your arrows. You can determine the optimum KE for the energy stored in your bow by chronographing arrows of different weights. Arrow weights are expressed in grains (grs). You will find that extremely light arrows are not capable of fully absorbing the energy stored in your bow. Conversely, extremely heavy arrows will not provide the optimum KE either. The optimum KE is a value where the weight and speed values provide the best KE possible. Enter your values in either of the two calculators below.
Java Ballistic Calculator
Enter any two values, then click the "Calculate" button:
Weight (grs)
Velocity (ft/sec)
KE (ft/lbs)
Note: "Clear" old values for recalculation
KE=M * v2 / 450,240
.XLS Ballistic Calculator
Easton's Recommended KE for Specific Game Animals
KE
Game Animals
< 25 ft. lbs.
Small Game
25-41 ft. lbs.
Medium Game (deer, antelope, etc.)
>42 ft. lbs.
Large Game (moose, elk, black bear, etc.)
Many large animals have been cleanly harvested with less KE than advertised in this chart. A well placed arrow is usually the determining factor in a clean harvest. Consult the game regulations in your area for minimum DRAW WEIGHTS for specific animals (i.e., deer - 40 lbs/moose - 50 lbs, etc).
