Hunters develop loyal attachments to cartridges based upon subjective criteria.

The .300 Win Mag is an excellent cartridge. But you'll have to come up with new material because no one's buying that it'll kill deader than a 7MM Rem Mag. In fact, I'd go with 175 grain .284 caliber bullets as winning penetration contests.

Whoever wrote that the 7MM Rem Mag is the biggest gun most shooters can shoot from benches without flinching was on target. I've seen well put-up dudes flinch like old women when firing 180 grain .300 Win Mag bullets. And they ain't gonna kill any deader than 160 7MM Rem Mag bullets.

Go with a 7MM Rem Mag.