Yep... everybody oughta know by now that anything less than an '06 with 180 grain boolits just bounces off of animals. I reckon that we oughta make a law against hunting with anything smaller, lighter or slower! Goodness... how can anyone even THINK of hunting deer with a .308 and 150 grain boolits? Shame on you all that do! Might as well be usin' a pea-shooter or throwing rocks... Them 165's are just barely, possibly acceptable. Maybe only on the perfect broadside shot at 100 m or less with no wind and in a fence so they can't run away if it only scratches them.
Dang, all jesting aside... it's all personal preference, no one is right! .270/7mm/.280/.308/.30-'06/.300/.338 all shoot sufficiently flat for 300 yds. All have sufficient energy for 300 yds. All come in regular or premium bullets. Pick the one you like and shoot it. If you want to hunt brown bear you might want to step up a bit in size/energy... or at least invest in body armor. If you want to hunt elk, pick a better bullet and make a good shot. If you want to hunt moose, same thing. The key is in the shot placement. An 180 grain '06 won't kill a deer with a bad hit any faster than a 120 bullet in a .270. Take out heart and lungs and they die, doesn't matter if it's a pronghorn, a hog, a whitetail, an elk or a moose.
It's all in your choice. I use any of the following for deer; 6mm Remington, '06,.308 Win, .45-70, .357 mag, .50 cal, .45 cal, 12 ga, 20 ga, .376 Steyr and I'm sure I missed one or two... For hogs I don't choose the 6mm Remington and .357. It would work but I like a bit bigger bullet for hogs. If I was gonna hunt elk or bigger I would leave off the 6mm and .357 mag. I wouldn't feel undergunned against black bear with the others either. For Brown Bear or other dangerous game I'd take a .45-70 or my Steyr. That's the beauty of it all... I can have what I want for whichever use I want.
Of course I could have saved a BUNCH of money by keeping only the .30-'06 from the beginning. It was the first I bought since it would do just about anything. But hey, I like my guns and buy one or two a year just as a matter of principle. Pretty sure that I need a 6.8 spc. I KNOW I need another .44 Rem Mag. I could certainly find a use for a Drilling. A 6BR would be good too. I definitely have to get a 6.5x55 too. After that I might need something more like a .416 or bigger. Kinda crazy but y'all know it's just an addiction that has to be satisfied... dang I clean forgot about all them lever-actions I want...
ngh