I agree with Stalker. I know funds are tight for you but
I wouldn't limit myself to one role. Keep your AEG and save up for a bolt action if you want. I tend to take on an assualter's role for shorter games and when there is no use for a sniper but take on the sniping role for longer games. You need to figure out why you're not hitting your targets. Is your barrel clean, hop up set up properly, etc? Practice, practice, practice using a paper target at different ranges starting from 25 feet and working your way back. See where your accuracy drops off and adjust for it.