Free: Contests & Raffles.
Yes I know lots of people use it with great success on elk, but I'm a new hunter and not totally confident in my shot placement ability yet.
Out of those 3 I would go 7mm mag. I own 2 of them and a 270 for the wife. I have taken 2 deer the past 2 years with the 7mm mag with no damage to meat. I shoot Barnes Tipped TSX. 140gr and that is all you need. In my opinion.
At the end of the day... the 7mm is by far the most versitile of the three you mentioned. All three are nearly equal in recoil... factory ammo is readily available... and relitively inexpensive. Just make sure you buy the RIFLE that's right for you... this is far more important than the caliber... buy at least a couple boxes of rounds, and spend some time shooting in the field off sticks, backpacks, sitting, prone, etc. You'll be much better prepared when that time comes to point the rifle with bad intentions... at that point it won't matter much what caliber you chose.
but that's like eating the wrapper off a crayon anyway.
Ohhh... I disagree... other than the slightly better availability of the '06. Dispute the numbers posted above... then we'll talk. The '06 does have the advantage of stepping up to the 200-220 grain bullets... and those might be nice in grizz country... other than that, a 200 grain .30 cal bullet at 2600 won't do anything that a 175 7mm bullet at 2900 can't do.