I hunt the west exclusively where long range shooting is a given, and I have purchsed and shotseveral rifles and calibers through the years including the 06, 7 rem mag, 300 win mag, and 270. Ihave since taken to carrying a 308 almost exclusively (latest is a Weatherby Vanguard SMOA synthetic and stainless w/ a LoapoldvarixIV 4.5 x 10). With the newer amunintion i.e. - Hornady light magnum,the 308 and the 06 are identical - 3,000 fps for a150 grain out of a 24" tube. "Factory"difference is - 308 = 2,820 vs 06 =2910. So, pretty much a push there as well, out to 300 yards +/-.However, I did purchase the300 for bear, elk, and larger game simply because I can generate more energy with heavier bullets. Irregardless, I would be unafraid of anything short of big bear with the 308, but I would probably shorten my "comfort" distance down somewhatfor large framed animals.Oh, and boy oh boy is is ever asweetheart to shoot.

Also, about calibre, energy, accuracy, sightings, etc, the following links are two of theverybest I have ever read,and theyvery much mirror how we have approached thing son our ranch and with our hunters. http://www.kifaru.net/cartpwr.htm
http://www.kifaru.net/posimag.htm