minimum impact energy

Myth Busters: Minimum Impact Energy – Ron Spomer

Live the Legend |

Gun writer Ron Spomer helps shooters sift through some of the misinformation, and just plain misunderstandings that are traded among shooters and hunters as fact. In this myth buster from the Winchester catalog, Spomer tackles the misguided notions surrounding “minimum impact energy,” generally as it relates to the humane taking of game.

Spomer explains: “In an effort to prevent less informed hunters from attempting shots at large game with inadequate bullets or caliber rifles, game departments in many states began creating rules that created minimum standards for the guns and bullets that could be used on certain game. The problem is, they couldn’t all agree on what those minimums should be. Some opted to outlaw bullets for deer-sized game smaller than .243. Others sought to restrict ammunition that didn’t generate at least 1,000 ft.-lbs. of muzzle energy. Somewhere a consensus grew that 1,000 ft.-lbs. was the minimum energy needed to reliably kill a deer and that 1,500 ft.-lbs. was the absolute bare amount needed to cleanly take down an elk.”

The reality, Spomer writes, is that the .22 Long Rifle—a rimfire round—has been used to poach thousands of deer, elk, moose and even polar bears since its creation. He is even aware of one case where an elephant was taken with a .22. Is it ideal? Hardly. But the point it underscores: proper bullet placement and terminal performance as measured by expansion and tissue damage are way more important than impact energy in foot-pounds.

The truth is every bullet will eventual slow down to a velocity at which it no longer carries 1,000 ft.-lbs., but if placed in a vital area will likely still bring down a deer or elk. For example, the 158-grain .357 Magnum, a popular deer hunting round with handgunners that accounts for many deer each year, packs just 428 ft.-lbs. of energy at 50 yards and only 361 ft.-lbs at 100 yards.

When shopping for ammo, don’t place undue importance on impact energy as much as being able to shoot the load accurately and knowing where it will hit at various distances. Also, simply seek out a load with a good bullet, such as Winchester’s Power Max Bonded or Ballistic Silvertip, and you will be good to go.