RE: 300 win mag
I've been using the .300 WM for all those and Antelope/deer sized animals for years now. Yeah, recoil kind of sucks. But I didn't buy it to go plinkin'! I bought it because of it's superior trajectory at long ranges, bullet variety, knocjdown power at greater distances and cause I don't like to chase 'em after I hit them.
No more damage to meat than other calibers. I did move to premium ammo with bullets that open quickly (balistic tip Winchester) and that made a huge improvement. I've done more damage on a deer with my 30-30 than ever did with the .300.
I did put a better recoil pad on it, and I know guys that go with a muzzle greak also to reduce kick. But I don't worry about it, you can't when there some meat in the cross hairs!
You will love it!