Based on the general equation for kinetic energy, Ek=½mv2, which directly uses mass (m) and velocity (v), the following formula is used to calculate the kinetic energy of a projectile (expressed in foot-pounds):
E=(W*V2)/(14000*gc).
In this formula, W = weight of projectile, in grains; V = velocity, in feet per second; gc= gravitational constant, 32.174 ft/s2