My first real hunting gun that was MINE, that I bought; was a Rem 700, stainless synthetic in .270. I think it's just a great chambering; and one that I prefer to almost any other. After I bought it I started Reading Jack O'Conners old stuff, and others, and I came to agree, it's the best all-rounder standard bolt action chambering.
I grew up with my .270. Perfect for almost all North American game. You can shoot close and not tear up a whitetail, or you can reach out for a long shot and still have enough moxie on the bullet for an elk (I was turned on to the round by my elk-hunting uncle).
The reason why I would probably go with .308 though, is for ammo commonality. I already have a .308, and several thousand rounds of ammo for it; plus I plan on reloading it.
I know the .270 is sufficient for elk with the right load selection, and at the right range (and really the .308 isn't beyond 250 yards or so), but it's just not quite where I feel comfortable with it. I'd like that extra 100 or so yards of safe killing range that the magnum is going to give me.
Given that, I really do think if i decide to go for elk again; that I'll buy a 7mag. The new .270 mags (theres three of them I think) are interesting; but ballistically they seem to offer little advantage over the plain .270, and a slight disadvantage(in bullet weight selection) to the 7mag.
The various .300 mags, (including the short mags) are also interesting; and with some of them I can share bullets with the .308 if I decide to reload; but other than the .300 win mag theres a cost issue (the .300 is about the same cost as the 7mag), and the .300 is significantly harder kiciking than the 7.
The thing is, I don't see enough ballistic advantage in either the short mags, or the .300 mags over the 7mag to compensate for the extra recoil and/or the ammo cost and distribution issues. I like to follow the wal-mart rule on ammo: if you can't find it at your local wal-mart, it's not a chambering you want to depend on as your field gun; and 7mag is the most popular centerfire magnum rifle caliber in America (with .300 win mag right behind it).
I'm willing to be convinced, but thus far no-one is really arguing against me.
