Have you ever wanted to compare a fast lightweight bullet to a slower heavy bullet to see which one hits harder? Just enter your bullet weight below and its velocity. This calculator will display the Foot Pounds of Energy FPE and help you compare the power of different loads. (BULLET GRAINS x VELOCITY SQUARED) DIVIDED BY 450,436. 180GN x 1000 FPS SQUARED = 180 X 1,000,000 = 180,000,000 180,000,000 / 450,436 = 399.61 FOOT POUNDS OF ENERGY