NWTHunter said:
My personal bias is to the 7mm Remington Magnum.
It can efficiently kill anything in North America, with the possible exception of large coastal grizzlies and polar bears (I wouldn't trust a 300 Win Mag for them either); it has an effective killing range that extends beyond the distances that most hunters can or want to shoot large game; and, it does this with a relatively manageble recoil. It combines all the ballistics and killing power that most of us need, in a package that is easier for most to handle, relative to the 300 Winchester Magnum. No wonder the 7mm RM is the best selling magnum.
IMO the 300 Winchester Magnum is an awsome calibre but it doesn't provide any tangible advantage in most situations for most hunters. There is no doubt it packs more punch, but realistically do you need more than what the 7mm RM offers?
I couldn't have said it better myself

NWTHunter! I'm a recent convert to the 7mm Remington Magnum fanclub. Before that I was a true .30 cal fanatic. The .300 Win Mag was the ultimate hunting round for me at least until I tried a 7mm RM! I had intended to pick up a new Sendero in .300 Win Mag...I had been wanting one for ages and with Remington's decision to drop the Sendero, I figured I'd better snap up a left-over fast. Then the 7mm got in the way. I picked up an older Remington 7mm BDL, intending to strip if for the action, but decided to shoot off some ammo I had laying around from another trade. I found myself really taking to the rifle and cartridge combo! In fact, I used this same rifle, with the addition of a new LSS laminate stock and trigger job, to take my Moose this Fall! My hunting buddy also used a new 7mm RM Stevens, shooting a Remington 175gr Core-Lockt factory loading. I was shooting my own handloaded Barnes 160gr X-Bullet. Both were one shot kills!
The 7mm is much more pleasant to shoot than the .300 and gives very little up, in terms of practical range and stopping power. It doesn't take much to kill a moose...the tens of thousands that are killed each year here in Newfoundland with the venerable .303 British round is testament to that! In terms of accuracy, the 7mm gives NOTHING up to the .300 Win Mag! I became such a fan of the 7mm, that instead of picking up that Sendero in .300 Win Mag that I've been wanting for years, I went with the 7mm Remington Magnum instead!
As for bullet selection...there are tons of different bullet weights and styles available for the 7mm today...Just look at the selection Bartell just sold in the Equipment Exchange yesterday (still smarts that I missed out on that deal Tod!

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I wouldn't feel undergunned or at a disadvantage taking to the field with either caliber, but I have to say that the 7mm is the more shootable of the two, especially for newbies and guys who fire less than a couple of boxes of ammo a year. Sure you can go heavier with the .300 Win Mag, but almost every guy I know who hunts with the .300 Win Mag shoot 180 gr bullets, - rarely do I see any 200 or 220 gr. bullets in the field hunting Mr. Moose! Besides, I haven't met a Moose yet who could tell the difference between a 175gr 7mm RM bullet and a 180gr .300 Win Mag bullet!
