A gun pundit once wrote a fine article ( and I cannot find my copy) arguing a specific range of calibers in specific wieghts moving at specific velocities were required to confidently drop Bambi, Bart or that other obnoxious varmint.The all very good arguments also have a few caveats. True, the '06 can be loaded for everything from squib loads to varmints to deer and finaly bear ( Hemingway carried a Griffin and Howe .30-06 as his 'big gun' in Africa FOR CAPE BUFFALO.)But a RIFLING TWIST and throating that will stabilise a 220 grain bear load may prove mediocre with a 55 grain spitzer. And some people simply have different thresholds of recoil control, nothing unmanly involved. I find the .375 H&H a slow shove, while Weatherby cartridges seem an exercise in masochism. The 220 grain 06 was in fact standard 'bear medicine' in Alaska for many years until magnumitis overwhelmed common sense. I was part of a party with the grim task of killing a rather nasty Kodiak after he mauled a tourist. And it was my shot to the vertebrae that ended his life. My rifle that day happened to be a 7 Mauser loaded with a 174 grain roundnose, a combination considered a smaller equal to the 220 'o6. A post mortem found the poor animal carried a virtual display board of bullets in .30 .338 .35 and .375 calibers totalling well over a dozen poorly placed bullets. In the end, it comes down as much to the shooter as the weapon system of rifle and cartridge. Some people just 'connect' with a combination.In fact, the phrase 'Beware the one rifle shooter' is so true. I have a friend, WW2 Marine. He owns a pristine early Arisaka with intact Crysanthemum, bayonet and Norma ammunition. He routinely puts 5 rounds into the bull against guys with all manner of dedicated match rifles with scopes.