Re: What to learn more
sticky, there are a number of good books and manuals the BRM is good, also 23-10 (sniper training manual) can be very helpful. For snipers and sniper craft, The Ultimate sniper is very comprehensive but expensive ($60). For just ballistics, Understanding firearm ballistics is pretty informative but you'll need lots of coffee and red bull to keep falling asleep.
After you do a little reading and your starting to grasp some of the concepts track down a school near you and look into some professional instruction, where do you live?. The long range discipline of shooting is especially tricky and a good instructor has ways some simplifying the information as well and tuning in your shooting.