The Myth of Muzzle Energy
By Mike Hudson
Prior to the introduction of magnum cartridges, muzzle energy was not the hot topic of conversation that it is today. In fact, many riflemen of the era didn't even know what it was while others, who knew what it was, dismissed it as unimportant.
Writing in 1948, the famed African poacher and remittance man John "Pondoro" Taylor stated that energy was "Surely the most misleading thing in the world where rifles are concerned. Gunsmiths invariably quote it because, particularly since the advent of the Magnum, it is decidedly flattering to their weapon."
Taylor quite likely killed more game animals, including dangerous game, than any half dozen men you're likely to meet today. (Taylor's experience was deep, but quite narrow. He had, for example, virtually no experience hunting outside of British Colonial Africa. -Ed.) He was writing at a time when nearly all of the important standard velocity cartridges, and many of the larger magnums, were already in widespread use. Why then was he so dismissive of what many riflemen today accept as gospel; that muzzle energy is the single most important determining factor in ranking the killing power of the various calibers?
"Muzzle energy is far too dependent upon velocity and tends to ignore bullet weight," Taylor wrote. In researching the question, I cracked open my dog-eared copy of Jack O'Connor's "The Rifle Book" to see what the Dean of American Gun Writers had to say about muzzle energy. Not too much, as it turned out. (In other publications O'Connor defended muzzle energy as less misleading than "pounds feet" and other momentum based yardsticks. It should be noted that O'Connor shot quite a lot of African game, including all of the Big 5, in the course of his dozen-plus safaris. O'Connor hunted all over the world in all conditions and accumulated a far wider base of experience than Taylor. -Ed.)
O'Connor, often regarded as the Godfather of the lighter bullet, higher velocity school of thought, saw the advantages of such a combination primarily from the perspective of achieving a flatter trajectory and longer effective range. This makes sense, as O'Connor did much of his hunting in the Rocky Mountains and open plains of the west. While a 200-yard shot was a very long one for Taylor, O'Connor regularly killed game beyond that distance. Two philosophically different hunters writing about different kinds of hunting.
Today's shooters are lead to believe that energy is the main determinant of some mythical "knock down" power and often fail to take bullet weight, design, sectional density and, most importantly, proper placement into account. Of course nothing could be further from the truth.
While energy calculations may be of value when comparing various loads in a single caliber or similar calibers, they can be worse than useless when comparing different calibers and different hunting situations. To illustrate the point, let's examine a couple of rounds, one being a wildly popular high velocity round in wide use today and the other being an outmoded and forgotten dinosaur.
The .243 Winchester fires a 95 gr. spitzer bullet at 3100 fps in one popular hunting load, producing 2021 ft. lbs. of muzzle energy in the process. Many thousands of hunters arm themselves with .243 rifles and kill an inordinate number of deer and antelope every year. (Thereby demonstrating its effectiveness for such use. The .243 is also quite popular in Africa for hunting game animals of similar size. -Ed.)
On paper, the .243 also stacks up great against an old cartridge like, say, the .303 Savage, which launches its flat nosed, 190 gr. slug at a MV of 1980 fps and achieves a paltry 1650 ft. lbs. of energy at the muzzle. The informed observer might further note that the old Savage round is obsolete, meaning it isn't loaded by any of the major ammunition manufacturers anymore, and that rifles chambered for it haven't been manufactured in many years.
Based on this alone, it would be easy to conclude that the .243 is the far better game getter in most, if not all, hunting applications. As with most easy conclusions, however, this one depends entirely on the application and situation.
A lot of factors may have played a role in the ascent of the .243 and the casting aside of the .303 Savage, but muzzle energy shouldn't have been one of them. Experience has shown that, at ranges of less than 150 yards where trajectory isn't much of a factor, a hit from a 190 gr. soft point slug is going to bag a lot of game. At those ranges and on game larger than pronghorn antelope and medium size deer, a well placed shot from the old .303 beats a well placed shot from the .243 every time.
Think about it. While neither caliber would be appropriate for dangerous game, if you found yourself suddenly and uncomfortably up close and personal with a grizzly bear, would you feel better with a .303 or a .243 in your hands?
Out past 200 yards, the .303's rainbow trajectory comes into play and the less than aerodynamic shape of its bullet compounds the effects of gravity. It is only then that the flat shooting characteristics of the .243 come into play.
Such comparisons could be made all day, and are not meant to denigrate the many sportsmen around the world who have chosen the .243, or any other caliber, as suitable for their purposes. They are used merely to point out that fallacy of using muzzle energy, or any other purely theoretical consideration, as some kind of be all and end all when it comes to killing power.
Copyright 2007 by Mike Nelson. All rights reserved.