As most NC PS2 players know, the Jackhammer burst-shotgun was significantly retooled for Game Update 11. It's one of the faction-specific heavy weapons (the others being the VS Lasher and TR Mini-Chaingun). Wrel also argues that the changes have effectively shifted it from a low- to high-skill required weapon.
More generally, NC weapons tend to have a close range, high-power bias. NC Maxes, for instance, perform exceptionally well indoors (at, say, Biolabs) but have difficulty fighting TR and VS troops outdoors.
Thanks again to Wrel for this video!