I've found with the sniper rifle a well placed shot to the head or chest will take out a KPA np. Same with the Gaussing (sp.?) gun. One shot they're downTwo shots for the KPA nano suit guys. Up close you gotta aim for the head and be on target. Shooting while running with the any automatic rifle in this game is less than favorable IMO. On the other hand the shot gun can be surprisingly accurate at a distance? I'm playing on "normal".
I've love running into a room with 2 or 3 KPAs and unloading the shotgun into them hahaha.. never knew what hit em.