Choosing a cartridge with too little Terminal Medicine could result in a severely wounded animal suffering unnecessarily for hours, weeks or years. No hunter wants to be responsible for such suffering.

There have been many formulas to help hunters select a cartridge for specific game animals. Some have been accepted and others have been ignored. No previous formula has ever been successful in aiding cartridge selection across the full gamut of game that the world offers to human hunters.

Usually the great failing of such formulas has been addressing the gigantic game animals. Hippopotamus and rhinoceros are huge, to be sure, but elephants are gigantic.

The Terminal Medicine formula was developed specifically to aid in the selection of bullets and cartridges to be used in the sporting pursuit of gigantic creatures. Not just giant game animals like elephants, but even giant predators. After all, elephants can become quite predatory at times. When this behaviour presents itself, the amount of Terminal Medicine required for a successful hunt increases.

A large bull elephant can be as imposing a threat as an average size Tyrannosaurs rex might have been. Most people would approach a hunt differently if they considered that a rogue or murderous bull elephant posses as great a threat as a T. rex.

It is always better to overestimate ones foe than to face the disaster that can result from underestimating one.

If you treat every bull elephant as if it were a predator of equal size and weight, no elephant will ever catch you underestimating him.

And if some resourceful fellow ever does bring Tyrannosaurus rex back to our world you will not underestimate it and go gallivanting off to save the world with an M-16 only to discover what the inside of a T. rex mouth looks, smells and feels like.

Adequate weapon selection is always important; the situation and the game dictate the necessary armament. An M-16 might not be appropriate for the stalking of a T. rex but one would be a good choice if stalking a platoon of armed rebel soldiers.

To be adequately armed for the sporting pursuit of a typical six ton bull elephant whose behaviour has turned predatory the Terminal Medicine formula (abbreviated: T.Rx) suggests cartridges with a T.Rx value of 81 or higher. Cartridges such as the 450 to 470 Nitro Express group (T.Rx range: 81-85) meet this criteria. Interestingly enough, so does the 8-bore rifle firing a brass cased 875gr. round ball at 1,650fps (T.Rx 83).

Never before have we had the means to be able to accurately compare the effectiveness of a classic bore-rifle firing a lead ball to the cartridge rifles firing jacketed bullets that replaced it. Yet hunters from the turn of the nineteenth to the twentieth centuries told us that these cartridges were comparable based on experience.

Most hunters of that era switched to the deeply penetrating 450 to 470 group of cartridges right out. That those cartridges were lighter weight and less voluminous than their bore-rifle counterparts certainly helped as this allowed for a greater number of cartridges without increasing the weight to be carried. More cartridges meant more game and that meant more profit. It was a simple decision really.

Still, some hunters did not make the switch. Some did not feel that the new hot-burning smokeless propellants required to push the little jacketed bullets fast enough to equal the effectiveness of a trusted black powder 8-bore rifle with which they had already had such great success was really worth it. Many hunters used such bore-rifles well into the smokeless era, with great success I might add.

Terminal Medicine was developed to aid in the selection of cartridges and bullets for the giant creatures, but surprisingly, the Terminal Medicine formula seems to work when selecting bullets and cartridges for game of all sizes and scales; for predators and game alike.

Some examples of Terminal Medicine suggested values and cartridges are illustrated below:

To be adequately armed for a 140 pound deer (T.Rx 29-37) the formula recommends cartridges such as .243 Winchester (T.Rx 29), 450 Black Powder Express deer load (T.Rx 33) or .303 British (T.Rx 36).

Turn that deer into a 140 pound predator, say a Leopard, (T.Rx 42-50) and the formula suggests for adequate armament such cartridges as .308 Winchester (T.Rx 42), 12-bore Paradox lead ball load (T.Rx 46) or 9.3x62 Mauser (T.Rx 50).

The Terminal Medicine requirements for game are lower than for predators, thus the T.Rx range for the Leopard is also adequate for a much larger game animal, such as a 625 pound elk. This emphasizes the need to differentiate between game and predator when choosing a bullet/cartridge combination.

If that 625 pound beast is a tiger (T.Rx 55-63) then the bar is raised again. The Terminal Medicine formula suggests that adequate armament for such a tiger includes some legendary cartridges: 9.3x74R (T.Rx 56), 375 Holland & Holland Flanged Magnum (T.Rx 60) and 375 Holland & Holland Belted Magnum (T.Rx 63).

These few examples clearly demonstrate how the Terminal Medicine formula can be used to aid a hunter in the selection of an adequate rifle cartridge and bullet for the game to be pursued. It offers clear and accurate guidance whether selecting a rifle to stalk that tasty white tail deer out on the back forty or when preparing to stalk a murderous lion or elephant that is terrorizing an otherwise peaceful village.

As a final thought, it is important to remember that the Terminal Medicine formula is calculated using solid or jacketed bullets because the terminal performance characteristics of expanding bullets is, from the moment of impact onward, a fluid, changing and unpredictable data set.

This does not indicate that the formula is of no use when the hunter intends to select an expanding bullet for a hunt. Provided the expanding bullet has adequate penetration characteristics for the intended game it can simply be said that the expanding bullet will perform at least as well as a jacketed or solid bullet where all other measures are the same (calibre, bullet weight, bullet speed, etc.). It is quite likely that it will perform better.

Hunters must beware unrealistic expectations and overestimation of bullet performance. The awesome power of Thor’s hammer, to strike an opponent instantly dead, has yet to be replicated. If the "magic" expanding bullet fails to perform as claimed then the resulting effect on the game animal will be quite similar to that of a jacketed or solid bullet. To know that the cartridge and bullet chosen are enough, even in such a circumstance, is critical to a successful hunt and the hunter’s peace of mind.

The Terminal Medicine formula is much too complicated and involved to explore in depth in such limited space. To learn more about the T.Rx formula and how to use it to select a Minimum, Adequate, Proper, Improved, Superior or Stopping rifle and cartridge please consult the book rexGun (by Dr. Stephen W. Templar; Ivory Lady Publishing 2008; ISBN: 978-0-615-22413-8).