Accurizing the Factory Rifle - by McPherson I believe, will give you a great idea of what it takes to turn a factory rifle into more of a tack driver. Some of it is dated ( inserting a liquid filled vial into the stock to ease recoil is no longer used ) but it is well written and will give you some great pictures to go with the wisdom.
Ultimate Sniper by John Plaster is an excellent book on shooting, ballistics, scope settings ( cant, windage, elevation, lead, hold over, etc ) and will really teach you a lot about shooting a rifle.
I have both in my library and still open them from time to time just to double check things.
JD