But seriously...
.30-06
Over 95 years old, it remains America's favorite hunting cartridge.
After a dozen Alaskan hunts, more than 20 Canadian ones, 30 African safaris, a dozen European hunts and God knows how many in the United States and Mexico, I have some experience with most of the cartridges we consider "all-around" choices - rounds that will handle darn near any situation short of very large and very dangerous game.
I have shot the .270 Winchester a great deal, and I like it. I have shot the .280 Remington a great deal, and I like it as much. I have taken some of my most memorable trophies and made some of my very best shots with a 7mm Remington Magnum. I like it very much. I have also hunted quite a lot with both .300 Winchester and .300 Weatherby Magnums, and I respect both cartridges immensely.
I have written positively about all of these cartridges on more than one occasion. But if I were forced to choose one, my preference would be the .30-06. And I am not alone. It remains America's most popular hunting cartridge - and those who choose it are not wrong.
Part of its popularity must be credited to its lineage. It was America's service cartridge through two world wars and countless skirmishes. But its current and lasting popularity is based on much more than its military heritage, as we shall see. First, however, let's take a fast historical look at what we call the .30-06 Springfield.
It was originally designated the "Ball Cartridge, caliber .30, Model of 1906." The great Springfield rifle was just three years old, and had been chambered to a very similar cartridge firing a 220-grain round-nose bullet at 2300 feet per second. The 1906 version has a case neck shortened by .007 inch. The few remaining rifles chambered for the original ".30-03" will therefore chamber the shorter .30-06 rounds, but the reverse is not always so.
The 1906 version featured a 150-grain spitzer bullet at a then-sizzling 2700 fps. This was the load that saw us through World War I. In 1926, the bullet was changed again, to a 172-grain boattail at, initially, the same 2700 fps. Although this significantly improved the long-range performance of the Springfield rifle, the boattail bullet was actually adopted to extend the maximum effective range of the like-chambered light and medium machine guns of the day. The velocity was later reduced to 2640 fps. In 1940, with the changeover to the gas-operated Garand beginning, the original flat-base 150-grain loading was readopted.
The .30-06 remained our standard military cartridge until 1954, when it was officially replaced by the 7.62mm NATO round (.308 Winchester). However, it was 1957 before the first 7.62mm M14 rifles were actually fielded, and the .30-06 remained in use, especially for machine guns, until the 1970s.
One of the first recorded sporting uses of the Springfield rifle and .30-06 cartridge occurred during President Theodore Roosevelt's celebrated nine-month African safari in 1909. T.R. was ecstatic with both the Springfield and the cartridge, but it was some years before the Springfield action was available to the public in significant numbers.
The first sporting rifle chambered to .30-06 was probably the Winchester 1895 lever action, rather than a bolt gun. It was chambered first to .30-03, and then to .30-06 in about 1908.
By the late teens, early custom gunsmiths like Griffin and Howe in New York were doing a brisk business making custom .30-06 rifles on both Springfield and Mauser actions. In 1921, the Remington Model 30 was introduced in .30-06, as was the Winchester Model 54 in 1925. It was, of course, an initial chambering for the Winchester Model 70 in 1937, and for the next quarter century the Model 70 .30-06 was perhaps the most famous - if not the most common - production sporting rifle.
http://www.huntingmag.com/guns_loads/30_06_springfield/