Nonya, in all of my years hunting moose I have only seen or read about one hunter who took a moose over 350 yards out and his tool of choice was a 30-06 and 180 grain Nosler partition bullets.
If a person is going to purchase a new rifle and it is going to be a magnum type such a the 300 Win mag, they best know before hand if they can in fact handel the extra recoil this magnum delivers, many shooters buy the gun and then find out the hard way.........OUCH!!!
Thus their accurcy down range goes to pot because it hits back and they simply can NOT handle the recoil. Now 5 pounds of added recoil to the shooter is enough to break the camels back, so to speak. So my advice is buyer beware ahead of time what the recoil to your body is going to do to your shooting accuracy down range.
A 30-06 with a 180 grain bullet and MAX load, will deliver to the body some 26 pounds of recoil and for many shooters, that is their MAX threashold of pain as far as recoil goes before their accuracy falls apart on the target.
A 300 Win mag with a 180 grain MAX Load will deliver in the area of 31 to 34 pounds for recoil to the body and that is enough to spill the beans if the shooter is NOT ready for such abuse. Many shooters no matter how hard they try can NOT overcome recoil passed a given point and with many hunters that point is around 24 to 26 pounds of felt recoil to the body.
Many hunters after buying their so called Magnum Caliber Rifle, find out they can't really benefit from the added yardage it gives because they simply can't handle the recoil and their accuracy goes to pot. I hope you and others are getting my point made on this magnum caliber issue!
You don't buy that caliber without knowing before hand that you can shoot at least a dozen rounds from the bench, without it causing your shot groups to get larger. To do so would be to defeat the cause of trying to hit an animal passed that 400 yard range as I see this senerio. It takes a heck of a lot of practice before one can learn to handle a 300 Win magnum caliber effectively with excellent accuracy at 400 yard ranges.