Then pocket the second gun until the first runs out. If you've got a buddy, get the zombies coming through a fatal funnel. You shoot straight at the funnel whil

Then pocket the second gun until the first runs out. If you've got a buddy, get the zombies coming through a fatal funnel. You shoot straight at the funnel while your buddy reloads the inactive gun. This allows you to maximize accuracy while the lead never stops flying down the hallway (until you run out of ammo).