Im gonna go with victorcharlie here-
If your going for elk / deer and such, you really do not need the 7mm mag or 300 win mag esspecially for shots under 300 yards.
Look at it this way, a 30-06 has very good knockdown power on mostly EVERYTHING that walks north america (other than 1000 lbs bears), but I don't think your going bear hunting cause if you were, You would not be talking 7mm mag or 300 win mag, you'd be talking .338 win mag and up.
I tell this to everybody, a well placed shot is a million times more powerfull than any magnum, you just need to practise shooting alot.....30-06 is cheaper to shoot than both the 7mm and the 300wm, AND it generates less recoil......
So lets see, a round than can kill an elk just as fast as a 7mm mag or 300wm, generates less recoil, has a reputation of "the best hunting round in the world", oh, and costs less to shoot
..... I think a 30-06 is your new best friend
as far as rifle goes, I personally love, JUST LOVE semi-autos, so I tell you this, get your self a browning BAR in 30-06, you'll love it..... I have mine in .338 win mag and let me tell you, it kicks like a mule, but everytime I go to the range everyone's like "is a semi-auto .338 win mag ?".....
My first rifle ever was (still have it and shoot with it all the time) is my remington 7400 in 30-06, I wouldn't give it up for anything becuase it got me hooked on this sport