Thanks for all of the feedback.
While I havn't hunted in 13 years, I don't know if I'd consider myself a newbie. I did hunt for nine years before that. The reason I choose the 300 win mag is the fact that you can hunt anything with it. I understand that shot placement is far more important than calliber or bullet grain. I was asking because I was hoping to get some opinions on the different mushrooming effects in whitetails depending on bullet grain & makeup. I plan on useing 165 grain hornady sst. But if anybody has some insight why a particular bullet grain or composition would be better I'd love to hear it.