As far as I know, darts, arrows, and airplanes have the center of gravity(CG) ahead of their center of pressure(CP) and often have fins at the rear to achieve stability. Contrary to these, bullets have CP ahead of CG and they do not have fins. Thus, how do bullets acquire stability?
You may want to look up rifling - a bullet is made spin around it axis in order to give it stability. This is actually the main difference between a shotgun and a rifle - the former does not have a helical groove in its barrel and therefore is much less precise (although nowadays the distinction is probably rather blurred).