Camp the heavy ammo with a void sniper then go to town with a void machine gun. I was done in 8 matches. Play control because many blindly run to control points and you can pick them off. Scrub tactics but hey it works.

Void rocket launchers are also good for getting several kills at control points. You can judge the number of enemies at a control zone by how quickly the capture meter is filling then blast Truth into their faces for quick points. I wouldn't count on heavy ammo, though. Back when I did it, shotguns were the best way. That was before the first nerf, though. Today, I think I'd go with a fusion rifle or Atheon's Epilogue, obviously.