"A large, double-handed hammer itself is quite a weapon against the plague of those salivating tramps. If you add some load to it, throw in a couple gimmicks and run an electric charge through the head your enemies will launch on impact as if from a catapult."
Found in the Jungle, in the bunker just west of the Ghost Town, in the back room, on a desk. The Ghost Town is where you first see a Butcher. It is in the center of the map, just south of dead-end of fork off the main road.