RE: 300 win mag
a .300 win mag vs. a .338 WM I wouldn't worry about faster kills etc....but on teh big stuff, say grizzly I wouldn't use a .300, i would use a .338, or a .375, but 2 bullets going the same velocity, the bigger one should lose velocity slower than the ie 250gr bullets slow down slower vs 180gr, though you're also considering BC etc....a .338 is a great combo of big and fast, whereas the .300 tends to be more fast IMO, and .375 is more heavy than fast, a .338 I've heard called as an alaskan's all around, like in a alaska a man has a .338, in texas he may have a .270, in colorado a .30-06, in africa a .375, my vote is for a .338, though a .300 I dont see as overlap eventhough you have a .30 30 while it is a .308 caliber its less powerful than a .270, either way you go its a nice round, but I've just continue to love the .338, and also not eveyone has a .338, but seems like everyone has a .300 WM.