^^^^ This^^^^^

Remember, bullet selection is more important than the cartridge.

Personally, I've gone to Nosler Accubonds for everything but my .458 SOCOM.  They work very well up close and at distance and they are extremely accurate in every rifle I've shot them through.

I've been through a lot of different rifles and chamberings but I've settled on .458 SOCOM for a "brush gun", 6.5 Creedmoor for mixed terrain and deer-size critters, 7mm Magnum for open terrain and larger critters.

30-06.  There’s a big following for 7mm-08 but I want the extra ass I can get out of 180-200 grain rounds with an 06 if I’m going for elk.

.30-06, it is ubiquitous, can be found virtually everywhere and can kill virtually every walking, crawling thing. It is chambered in practically any kind of rifle you desire. I had a chance to buy a new rifle in any caliber I wanted and did alot of research, ballistics and performance aside, I came to my senses and followed my pragmatic instincts.

.30-'06. it'll kill anything in North America. It's a proven long range round also, it's what Carlos hathcock used most.

The best elk killer I have used is a 300WM, bar none.

8 elk with 180gr Accu-bonds. Dead right there, no need to track.

A truck load of deer, the white tails around here are dinky compared to the areas that have the big boys.

3 black bears, all 1 shot kills.

There is no wild life in the state of Montana that I would feel undergunned.

I'm older now and pretty beat up from my heavy fabrication, countertop and cabinet career so I can't take the recoil of the 300 anymore or it would be my #1 go-to.

280AI is my favorite.

I get velocities very close to 7mmMag with about 60gr of powder.

Just to follow up, I decided to go with 7mm-08 since that covers everything I want to hunt and has modest recoil. If I get serious about long-range shooting I'll likely go with 280AI or .284 Win.
Now if only I could find some ammo....

Excellent choice. Reading your OP I think the 7-08 will do everything you want even black bear.

7-08 with a eldx or nosler will kill all the animals. It's a great round and has been killing stuff for decades

Do you handload?
My guess is probably not due to your question. With that said some of the recommendations would probably not be practical.
  One of the posters mentioned going to the store finding out what you can get ammo for and buy that.  That’s pretty good advice these days.    Also be real about what you plan to hunt.  
Do you really plan to go on a Brown Bear hunt?  If the answer is no then a one caliber gun is doable.  If your going to get to hunt Elk or moose then I would say 30-06,  300 Win Mag, 7mm Mag since those are normally very common for factory ammo.
I dig the 35 Wheelen and .338 Federal but factory ammo may be scarce( or not)
I have multiple 45-70s but factory ammo is expensive and I don’t generally think of it as something I’d recommend to someone as their only hunting rifle.
The 6.5s,270s non mag 7s are all kick ass deer rifles but a bit light for Elk and Moose. They will work however if that’s what you want to go with.
At the end of the day there are many good choices.  If I could only have one hunting rifle and didn’t hand load .300 Win mag would be what I’d personally buy.

Yup. Except I’d do 300 WSM. Short action just feels right. Same ballistics.

300 wsm $3.50-4 per round when looking at Ammo Seek. Ouch
Other ammo seek search’s. Price per round is the cheapest.

30-06 $1.25 per round  
7mm mag OOS
.270 Win $1.75 per round
.300 win mag $2.25 per round
35 Whelen OOS
338 Federal OOS
45-70 $2.40 per round
280 rem OOS
7-08 $1.27 per round  

7-08 and 30-06 start looking really good if you don’t have a rifle or stash of ammo.

Missed this part
7-08 will serve you well.

That's a decent choice. I have a 270 and 308. I always end up taking the 308- in my case it handles better. Now I'm searching for probably a 300wm to reach out past my self imposed 350yd limit for elk.

Nothing wrong with 7mm-08 at all.

Of the cartridges you listed, 7-08.

It will do everything you mentioned from elk to black bear and down at the distance you stated and further.

30-06. It’s not “cool” anymore but it is definitely one of the most versatile and prolific calibers. Hand loads with modern powders can step the power up more than typical factory loads too.

This.

110gr for coyotes/varmints

150/165gr for medium game like antelope, deer, black bear.

180/200gr for elk, bear, moose.


You can find ammo almost anywhere in the works during normal conditions.

I would do 300wm, and actually go shoot the shit out of it..if you can't learn to shoot a 300wm, then go get a brake put on it and shoot more..06 and 308 really aren't much cheaper than the 300wm..they all share the same load other then a few pennies more powder per case which is what makes the 300wm the better cartridge, if you actually have to reach out for that trophy/meat bull, or you have a shit shot  for some reason..I went thru this argument in the 90's..ended up selling the 7's and the 300wm and went to 300rum, never looked back and wouldn't trade the cartridge for any other..a True take anything with one gun,  anywhere, anytime...