By Chuck Hawks
Having spent the time and effort to devise a rifle cartridge killing power formula that has a positive correlation with actual results in the field, it seemed appropriate to use that formula to compare the killing power of various hunting rifle cartridges and loads. Here is the G&S Online Killing Power Formula used to compile this list:
Energy at 100 yards (in foot pounds) x
Sectional Density (taken from reloading manuals) x cross-sectional
Area (in square inches) =
Killing Power Score at 100 yards.
Round off to one decimal place for convenience. (For more information, see
The G&S Online Rifle Cartridge Killing Power Formula and List.)
100 yards was chosen as a reasonable distance at which to compare rifle cartridges and loads, since most big game is killed within or around that distance. Switching to a heavy for caliber (high sectional density) bullet generally, but not always, increases the killing power score.
Long experience has shown the .44-40 200 grain/1310 fps MV load (KPS 11.0) and traditional .25-35 117 grain/2230 fps MV load (KPS 11.9) are adequate 100 yard deer cartridges, provided the hunter drives the bullet directly into the vitals. Consequently, I have inserted a line of demarcation between the Class 1 (animals weighing less than 50 pounds) and Class 2 (animals weighing up to 300 pounds) cartridges based on a minimum KPS of 11.0 at 100 yards. Consider cartridges/loads scoring below KPS 11.0, at whatever you consider their maximum effective range to be, as small game and varmint cartridges.
However, the Remington Managed Recoil .30-30 125 grain/2175 fps MV (100 yard KPS 12.9) and .357 Magnum (Rifle) 158 grain/1830 fps MV (100 yard KPS 12.7) loads are probably better guides to the minimum practical killing power for Class 2 game with more modern cartridges. Remington specifically states that their Managed Recoil .30-30 load is a 100 yard deer cartridge.
Therefore, I have chosen to use a minimum KPS of 12.5 for Class 2 game in many of my articles. For similar reasons, and being more conservative,
Guns and Shooting Online Cutlery Editor Gary Zinn uses a minimum KPS of 15.0 for hunting Class 2 game in most of his rifle articles.
When it comes to hunting larger game, a great many Class 3 animals have been taken by careful shots using cartridges/loads such as the .30-30/170 grain, 6.5x55/140 grain and 7x57/160 grain. On the other hand, most experienced North American elk hunters would probably suggest full power .270 Winchester loads (KPS 35+) as a practical minimum.
A 100 yard KPS score somewhere in the 30s is probably a reasonable figure for most Class 3 game, although less powerful cartridges/loads have long been used successfully. A KPS of 30 corresponds well with a Hornady HITS score over 901, which the experts at Hornady consider the minimum for use on large game.
The Alaskan Game Department considers the .30-06 shooting 220 grain bullets (100 yard KPS 54.6) a reasonable minimum for hunting Alaskan grizzly and brown bears, which are Class 4 (dangerous) animals. In most sub-Saharan African countries where dangerous game is still hunted, the 9.3x62mm/286 grain load (100 yard KPS 88.2) or the .375 H&H Magnum/270 grain load (100 yard KPS 106.2) are the recommended minimum for hunting lion, yet the big cats are about 1/2 to 1/3 the size of the great bears. Obviously, even among vastly experienced game departments, there is plenty of disagreement about rifle cartridge killing power!
