you might not want to start with bolt action as it is tiring and annoying if you miss. I would start with semi auto first, if you don't like that, then it won't get any better with bolt action.
i have played as an aggressive assault class for 2 years now and i find we are incredibly effective, but my combat machine completely jammed up halfway through a firefight, so i would like another some relxed role to play if that happens, i fixed the gearbox but i quiet like to be a marksman