Machinegun

The Machine Gun is a fully automatic rifle, it can fire 150 shots before breaking, and can be very useful against Special Forces who also carry it. It is visibly based on an M4A1 SOPMOD. The achievement "Perfect Gunner" is directly tied to this weapon, and requires the player to fire all 150 shots into a target without missing. Another simple way to get this achievement is to go to the underground butcher's shop. Aim the machine gun at a slab of meat hanging up. Fire all 150 shots at it to recieve the achievement. Be careful with this, however, as a miss will be much worse than missing a shot in 72-hour mode. The survivor Brett Styles is best with a machine gun, as he can kill zombies with a great range and comes equiped with this gun (one can, though not wise, give Brett "junk," such as an apple, to get it from him). Taking his gun is wise if one expects him to die.