Calibers

Thank God  I don't have too many people watching my site yet, as nothing gets hunters and shooters more worked up than arguing about the pros and cons of their favorite caliber compared to someone else's . When it comes right down to it, use any caliber you want because everything out there from your grand dad's old 30-30 to the 30-378 will knock down almost any big game animal in North America under the right conditions. I'm not going to get into the arguments with O'Connor fans who believe the .270 Winchester is the best, or get into the details of Elmer Keith fans who like big bore bullets for foot pounds of energy vice the fans of velocity. They're all good arguments and because they are, I own everything from 220 swift, 270, 30-06, 300 win mag, 300 weatherby, and 454 casull in both a revolver and lever action rifle. Pick the caliber that's best for you and use it to the best of its and your abilities. That being said (written), bullet selection and optics probably play a bit larger role than most people give credit.
I like packing my Winchester Model 70, 270 featherweight and my son's first rifle, which is a Ruger compact 77 in 7mm-08. I don't intend to use the .270 out beyond 400 yards, nor would I feel good about using the little 7mm-08 beyond 300. But they are both a pleasure to pack, which I do when conditions warrant it and I'm not in Griz country. My old standby is my Ruger 300 win mag fitted with a Leupold 3.5x10 VIII. It shoots well and has never failed to do the job. I like my 300 mag and an older customized Mauser 98 in 300 Weatherby, both rifles are comfortable to pack and offer me more than enough velocity and energy for Griz if needed. There are a lot of new ultra mag wildcat cartridges out there and many are now provided by major gun manufacturers.
Good examples are the 30-378 Weatherby, 338 Lapua and a virtual smorgasbord of others. If you like them and can hit your target with them, then by all means, use 'em. I'm a big fan of bigger is better and I do like velocity. I've shot the .50 cal Barret sniper rifle and while they are a blast to shoot, and you can wack "targets" from 1500-2200 yards, they might just be a bit overkill for sport hunting..  :-)
There are a lot of good bullets out there these days and it's been great that the major ammunition manufacturers have jumped on board and started making premium ammunition with some of the best bullets available. Examples are: Swift A-Frame, Sirocco, Barnes TSX, Nosler, etc, etc, etc. I happen to like the Barnes Tipped TSX. They shoot well out of almost all my rifles and although they do not expand a huge amount, they hold together and punch holes through damn near any part of a big game animal. I generally prefer lung shots on everything I shoot, but have been known to punch through both front shoulders to put them down hard and fast if the animal had the chance to immediately bail off into a steep timbered canyon full of dead fall. An animal going down hill with a lung shot can travel a long way before he runs out of air and can be very difficult to recover in some areas.
I have also used the TSX to punch through a large bull elk from stern to stem ( a "Texas Heart" shot, as close to anus as possible) when the only shot I had was his backside. The bullet entered approximately a half inch right and that TSX exited out his brisket and dropped him where he stood. The added benefit of the TSX and other full copper bullets is for bears. Griz have a heart rate somewhere close to 25-30 beats a minute, so shooting a bear in the heart, lungs, etc, may just not put him down quick enough for you to not soil your long johns. Breaking a bears motive power, that is, his front shoulders, appears to be the best way to stop their forward momentum. He can still push with the hinds, but he is not going to get to you very fast. I've never had to do this, so I'm not speaking from experience, so take it for what it's worth. Also,  not sure how you'd break those front shoulders if he's coming straight on. In that situation I'd probably start dumping rounds into his chest and lower throat and hope I could take out heart, lungs and maybe even get something into his spine.
I've seen a hell of a lot of articles and listened to a lot of people who talk about a caliber that is overkill for the intended species. Personally, I think it's all BS and here's my reasons why:

If I hit an antelope in the front shoulders with almost any caliber, I've just ruined both of those front shoulders, just as I would with my 300 mag. But my 300 mag maintains almost the same velocity at 600 yards as the 270 has at 400 yards (300=2241FPS at 600, 270=2319FPS at 400). It also has more foot pounds of energy at 700 yards than than the 270 has at 400 yards (300=1627FPE at 700, 270=1552FPE at 400). As I mentioned above, I like hitting all big game animals in the lungs when conditions warrant and if you hit the lungs with a solid bullet that animal is not going far with a hole punched through both lungs and you'll ruin far less meat if you do so.
The above ballistics were established with 300 yard zero, 32 degrees at 4000 feet. The majority of hunters sight their guns in with a 100 yard zero, but recently we've seen ammunition boxes listing 100 yard ballistics and what they term long range for 200 yard zero. I prefer to sight my guns that I intend to use at longer ranges with a 300 yard zero. This works well for me but may not be best for you. The biggest thing you have to remember is where that bullets point of impact is at closer ranges, not to mention having a range card listing bullet drop out to all the ranges to the end of your comfort range. I shot an elk once through the lungs at about 500 yards and when he went down, I moved in to about a 100 yards to finish him. I ended up shooting three times because it wasn't until after the second shot that I remembered my point of impact was +3 MOA at a hundred yards. What I intended to be a last shot through the neck and spine ended up hitting nothing but muscle till I remembered what the problem was. I felt bad for the bull and have never let the adrenaline rush let me make the same mistake twice.

Here's part of the reason why I like 300 vice 100 yard zero. The example is used with 300 win mag,  Barnes 168 grn TTSX, 32 degrees and 6000 foot elevation:

300 yard zero: 100 yd +3inches, 200 +4inches, 300 -.1inches, 375 -4.5inches, 400 -6.8inches,
450 -12.5inches, 500 -20inches

100 yard zero: 100 yd 0 inches, 250 +4.5inches, 300 -8 inches, 350 -13inches, 400 -19inches,
450 -26inches, 500 -36inches.

I don't know about you, but at 500 yards I'd much rather be doping a neg 20 inch drop than a neg 36 inch drop.
And I know, for those of you using tactical type turrets you don't care about the guess work of raising cross hairs above intended point of impact. You'll just dial it up to the correct yardage and let her rip, but this information is intended for those who have not shelled out a  thousand or two thousand dollars for that type Leupold, Night Force or Huskemaw, etc tactical scopes.

Tip of the Day: When you hit an elk and he goes down, but still moving, hit him again. If you feel you need to get closer just make sure you can see him all the time and hit him again as soon as possible. Don't lose sight of him because if he gets up and takes off you may be tracking him for days and you may or may not catch up to him. They are....a very tough animal.
Just my opinion, not that it matters...  :-)

Till next time, live well, hunt hard
Ron out