Coyote16,
Ther's more to good accuracy than you may realize. Everything works in conjuction with one another. If one item is sub par it throws a wrench into the works and accuracy suffers. I hear people say "I have a buddy who reloads, I'll have him make me up some reloads". What works for one rifle won't neccesarily work in yours. There's alot more but here are some key points to look at.
Rifle:
Assuming the chamber and crown are cut true, is the barrel 100% free floated sufficiently? Is the stock bedded, if it is, is it done stress free? Are my scope base screws tight? Is my scope rings lapped together for proper alignment? Is my scope of good quality that is reliable and repeatable?
Ammo:
Don't expect miracles from factory hunting ammo. Honestly with factory hunting ammo if you can shoot 1" at 100 yards in a factory rifle your fine. At 300 yards theoritically you should be able to shoot 3" but it will probably be more like 5". You just can't beat fine tuned ammo that is made for your rifle. The only way to get that is to hand load yourself, test different bullets, powders, primers, seating depth ect. until you find what your rifle likes.
I know you stated you were new to long range and I don't won't to overwelm you. Take it one step at a time, and do what you can to improve your accuracy. Have your rifle gone over by a reputable gunsmith and do what he reccomends to help your accuracy out. If you can find someone in your area that handloads and is willing to teach you, get with them and learn as much as you can. To me hands on is the best way. Other than that there is a wealth of information on here and almost anyone here will be willing to help as much as possible. Welcome to LRH and good luck.