The Mythology of the Correct Big Game Cartridge
It has been going on since the origin of hunting: the clumsy co-mingling of scientific terms and baseless speculation. We know that a bullet cannot knock an animal down, it would take a new branch of physics for that to be possible. Yet, the odd notion of “knock-down” persists.
We have an odd collection of various game formulas, and redundant references to “thin-skinned game.” Yet, virtually all big game animals commonly hunted do indeed have thin skin. Nor is skin in any way a vital organ from a terminal ballistics standpoint. To be sure, there are animals with thick skin. The white rhinoceros has skin 18 – 20 mm in the thinnest area, 45mm or more at the shoulder. While there is legal rhino hunting, buying a new house tends to be a better investment for most folks. Sadly for the rhino, it grows a large protuberance on his nose made of fingernail material for which some will pay a large some of money and has suffered heavy poaching as a result. For those clinging to the notion of the power of eating rhino horn, ingestion of their own toenail clippings apparently would give similar, if not identical, results.
ANATOMY AND PHYSIOLOGY
Above, the world's largest antelope, the eland.
The basic anatomy and physiology of deer family animals (deer, elk, moose), antelope (kudu, hartebeest, waterbuck, gemsbok, wildebeest, eland), horse (zebra), and bovines (Bison, Yak, Buffalo) is not dramatically different. A pig is a pig and a bear is a bear.
There are significant differences in mass, strength and the accompanying heavy bones and thick muscle associated with large animals, of course. No one would expect good results from a gut shot on an Impala, so poor shot placement on the heaviest antelope, the Eland, which weighs from 900 to 2000 pounds, cannot be expected to yield positive results.
There is no basis for considering the common Eland to be greatly different, as a game animal, than a 900 - 1200 lb. Newfoundland moose, or a larger example of the Giant Eland to be wildly divergent from a 1400 - 1600 lb. Alaskan or Yukon moose. Nor would the majestic Waterbuck or Kudu be wildly different, from a hunting perpective, from Rocky Mountain or Roosevelt elk.
Craig Boddington conducted two surveys of licensed African professional hunters, one in 1989 and the second in 2007. According to Craig, “In 1989 the 7mm Magnums were extremely popular, both as a professional hunter’s personal choice and as a recommendation to a client. The .30-06 also did well, but there was little support for the .270.” In 2007 this changed dramatically, as there was little support for 7mm Magnums, the old 7x57 was much stronger for “light plains game” (whatever that means), but the winner in this category was the .270 Winchester. This suggests that some hunters, including professional hunters, are just as bewilderingly fickle as ever.
IF I AM A .30-06, WHAT AM I?
That sums up the problems with assuming a cartridge means something. A .30-06 throws what bullet weight at what velocity? What is the bullet design in addition to that, and how long is the barrel? As for further variables, we have the age, sex, weight and health of the animal to consider, as well as the range at which the animal is taken.
One common .30-06 load is a 150 grain bullet that has about 2081 fps residual velocity at 300 yards, is Federal load #3006A. Just what is the difference supposed to be, to an animal, versus a .30-30 Winchester 150 grain load used at 100 yards (load #F3030FS1) that has 2086 fps velocity? The differences become weaker yet if, for example, you are using a .308 Winchester out of a compact rifle that has a 16-1/2 inch barrel length. You might well be throwing your 150 grain round at 2550 fps or so muzzle velocity instead of the 2910 fps with the .30-06 150 grain round, out of a 24 inch barrel.
OPTIMAL GAME WEIGHT FORMULA
Once you've created a proper wound track through the entire width of the animal, there is little else that can be hoped for. Penetration beyond this level is superfluous.
One of the better attempts at calculating the killing power of cartridges is the Edward A. Matunas “Optimal Game Weight Formula.” It doesn't withstand close scrutiny, as bullet construction, sectional density, nose design of the bullet and caliber are ignored and not represented in the formula. Game weight itself is no exact barometer of what you need in terminal performance. For example, an animal with a large, heavy rump and heavy legs to support it may well be heavy. Yet, rumpshooting is not part of good shot placement.
In the same way, a large and heavy headed animal, with a heavy neck to support the heavy head and associated headgear and heavy front legs to support the head / neck array may have nothing to do with where you are going to place your shot. Butt and gut weight can be significant, but the heavier animal may be no more difficult to quickly harvest. Kudu (420 – 600 lbs.) have a well-established history of being a somewhat soft animal, while the lighter black wildebeest (approximately 330 pounds) has quite a reputation for being extremely tough and tenacious, despite its significantly lighter than kudu body weight. For these myriad and sundry reasons, game weight alone defies simple formulas.
We already know the answer to that question. Karamojo Bell (Walter Dalrymple Maitland Bell) hunted lions for the Uganda Railway in 1897, when he was sixteen years old. W.D.M. Bell used a single shot .303 British rifle. Of the 1,011 elephants Bell shot during his career, about 800 of them were taken with the 7x57 Mauser (also known as the .275 Rigby). The 7x57 was a favorite of Eleanor O'Connor, wife of Jack. (It is also a favorite of G&S Online Staff members Chuck Hawks and Bob Fleck. -Editor) Today, one fairly common factory load for the 7mm Mauser is Hornady's Superformance 139 grain GMX bullet (B.C. of .486) at a published muzzle velocity of 2740 fps. Note that, despite the pedigree of the 7x57, the Hornady Superformance GMX 139 grain 7mm-08 load has a muzzle velocity of 2910 fps.
We know from the countless millions of game animals taken over the years and examination of projectiles hitting and crushing actual living tissue that Townsend Whelen had it right back in 1940: “The killing power of a bullet in flight depends entirely upon the average size of the wound it makes in the animal and upon nothing else. The size of the wound in turn depends upon the size, weight, construction, shape of the bullet, the velocity with which it strikes and upon no other details.”
The muzzle velocity, actual working ballistic coefficient and distance to the target determine terminal velocity. As long as we have impact within the working velocity of the bullet design (often 2000 fps and up in common .277 - .308 inch diameter hunting bullets) we are in very good shape. We need adequate penetration, of course, but as long as the bullet completely passes through the thorax of the animal, there is no possible benefit to more penetration. Bullet deformation is a good thing, but not at the expense of adequate penetration.
Flyweight bullets can only do so much with minuscule mass, so this all points to the notion of reasonableness. Reasonableness includes reasonable bullet weights of 120 grains or so at the low end, reasonable calibers (meaning bullet start diameters), reasonable deformation upon impact, reasonable wound tracks, reasonable impact velocities for the bullet design and penetration required, and proper shot placement.
In the area of common cartridges, chambered by a very broad spectrum of rifle manufacturers, you have the 6.5x55, .270 Win., 7mm-08, 7x57, .280 Remington, .30-30, .308 Win, .30-06, 7mm Rem. Mag., .300 Win. Mag., 8x57 (and more) that all do very much the same thing with the right bullet in the right spot. There are many other cartridges, not as generally mainstream or offering the broadest choices of rifles, loads, or widespread availability, that accomplish the same basic thing. Regardless of personal preference, little can live on the difference. Nothing ever has.
Copyright 2013 by Randy Wakeman. All rights reserved.