Buy a Savage Model 16FXP3 in .308 ,and when you can put 5 rounds touching at 100 yards, buy a better scope and move up to 300. when you can shoot 6 inch groups every time at 300, get a better barrel and move up to 500.
Then, if you want to shoot like a sniper, set up a target inside of 1000 yards.
Get a buddy, preferably that guy that gets on your nerves after a while, load up with 3 rifles and all your gear, and about 250 lbs of stuff. Pack along a few Oscar Meyer Lunchables.
Get on a bus, and ride it 12 miles out of town. Get off, and hide in the ditch till dark. walk back into town, hiding in the ditch every time a car passes.
If you don't make it to the range before sunup, hide in a dumpster the next day till dark.
when you get within 2000 yards of the range, crawl the rest of the way. If you have to pee, do it right where you are lying. Get to the line, and build a pillow fort. Hide in it with your buddy all the next day and night. Argue over who gets to take the shot, who's the better shot, the range to target, the wind speed and direction, and who ate the last lunchable.
Next morning, have your buddy call your girlfriend, and ask if you can take the shot. she'll tell you to call back a few times, then tell you no. pack up all your stuff (including your feces) and crawl all the way home.
While Precision Long Range Marksmanship is an important skill for a sniper, it's not the most important. Lots of excellent shots wash out of SSBC becuase they can't hack Mapmaking, stalking, Fieldcraft. Making the shot is the last worry- if you can't burn and hide, and wait and wait, you'll never get a chance to make the shot.