The three great cartriges of the world are really the 303 British, the 30-06, and the 8x57 Mauser. The reason behind this is simply because of the "Empirical Tendencies of the nations involved". Lots of rifles chambered for these rounds means that lots of rounds have to be produced to be shot through said rifles. Lots of rounds and rifles means that they have been tested on all sorts of animals all over the world.
The only reason why the 7.62x54r is not on this list is because it never gained widespread favor in the colonies for sporting purposes. Finland may disagree, but it's my opinion and I'm sticking to it.
The Short Magazine Lee Enfield is perhaps the finest of all the bolt action infantry rifles ever developed for one simple reason, a detachable 10 round box magazine. A Tommy could fire twice as many rounds as a Joe or Jerry in WWI and reload even faster. The 1903 Springfield and 1917 Enfield needed 5 round stripper clips, and the Gew98 took 5 round stripper clips as well.
The 303 British was quite a popular hunting round here in the United States for many years, ballistically between the 30-30 and 30-06. Plenty enough "umph" to take elk or black bear. I'd want something with more "umph" for Alaska, but wouldn't mind taking an SMLE along "for the pot".
The 30-06 became a success rather against the odds. I believe that had not two generations of American Fighting Men become indoctrinated to the usefulness of the 30-06 in WWI and WWII it would simply be another obscure loading. The 30-40 Krag is a fine round, suitable for the lower 48, but a scarcity of Krag rifles has doomed this round to obscurity. Due to German aggression the 30-06 stands alone as the round by which all others are compared. Powerful enough to kill most anything, recoil light enough that most people can handle it, commercial loads tailored to everything from prairie dogs to Alaskan Kodiak.
Then there is the 8x57. This round has a cult following here in the US mainly because of the availability of quality surplus Mauser rifles from various parts of the world. Everything that the 30-06 can do, the 8x57 can do if you handload. The lack of diverse commercial ammunition for this caliber is it's only real drawback. Both killing power and recoil are indistinguisheable from the 30-06. In spite of being on the losing side of two world wars this cartridge refuses to die simply because of it's inherent usefulness.
Often I think of these three rounds it brings up images of cool pre-dawn hunting camp. The heat of an African sun beating down on a hunter as he puts an eland in his sights. The blue sky above the Rockies dotted with clouds while a hunter decides that the old bull elk is just too pretty to take.
And then other times I am reminded of the lives wasted by empires enforcing the will of madmen. The poaching that pushes animals closer towards extinction. The suffering of those forced to live under the jack boots of a cruel and uncaring government.
But it beats the alternative. Can you imagine a world where my post wasn't about the 303, 30-06, and 8x57, but about the 7.7 Arisaka, 6.5 Carcano, and 7.62x54r Russian? How different would the world be?