What about all those deer that hunters have reported flipping over or blowing ten feet backward after solid, bone smashing hits from super magnums? Is that not an example of killing energy? No, it is not. More likely it’s muscular reactions to the impact. The animal leaped. Again, Newton’s law. If the shot didn’t knock you over, how the heck is the bullet — which has lost considerable energy during its flight downrange — going to have the power to flip an equally heavy or heavier animal into the air? Or push it back ten inches let alone ten feet?
Some of the misconception about this might be the fault of our kinetic energy measurement. A projectile’s kinetic energy (energy in motion) is a product of its weight and velocity. Doubling weight doubles energy. Doubling velocity quadruples energy. This is why 50-caliber blackpowder big game cartridges pushing 400-grain bullets 1,600 fps back in 1880 have been superseded by 7mms pushing 150-grain bullets 3,200 fps in 2021. The high velocity 7mm delivers more energy. (3,411 f-p for the 7mm vs. 2,274 f-p for the 50-caliber.) Most bottlenecked, smokeless-powder cartridges of about 25-caliber and larger throwing 120-grain bullets and heavier deliver more energy at 100 yards than do most the heavy, slow bullets of yesteryear.
To fully appreciate this we should define what kinetic energy in foot-pounds means: a foot-pound of energy is enough to, theoretically, raise one pound of weight one foot off the ground. A bullet carrying 3,000 foot-pounds of energy, then, should push a 100-pound pronghorn or whitetail doe a good 30 feet, right?
Killing the Energy-Killing Myth — Ron Spomer Outdoors is written by Ron Spomer for www.ronspomeroutdoors.com