You have time to get in shape so the added weight isn't enough to worry about. If the 300 isn't the winner in the accuracy dept,get working with it. Heck you own it,why not take it elk hunting? If not for elk,who needs a 300 anyway. Oh I shoot whistlepigs with my 300 Ultra,but I'm not normal. So they say. If you want to lighten it up a bit,the Bell & Carlson stocks are nice for the money. I worked my Ultra down to under 10 pounds field ready with one.
This is her on a breather in Colorado. My point is,if you own a 300 mag of some sort. Are planning an elk hunt. Why not put a little effort into it and make it the deal closer. I've had a few of each over the years,and wouldn't take anything away from the 30/06. But, the 300 is just tailor made for elk hunting.