Here is my advice/opinion so take for what it is worth:
I will use the analogy of cooking as akin to harvesting Elk.
There is no doubt a Winchester 300 sporting a 180 grain hunting bullet is plenty of Stove, burner and frying pan to "cook' an elk.
To paraphrase Justin Wilson when he was asked what kind of wine should I cook with? He simply stated "Cook with the wine you like".
So it is most important to shoot what you and your rifle likes! If you are gonna shoot your 300 win Mag a lot to find out what you like.... I would suggest you buy a PAST shoulder pad to cushion the recoil and help prevent flinching!
