The machine gun is the first weapon the player is given in POSTAL, and has unlimited ammunition. It has a moderate fire rate, and kills any enemy in around 10 shots. Most of the time, the machine gun will incapacitate an enemy, but they will die a few seconds later.
"The Machine Gun is the basic rapid-fire gun. Holding down the fire key will cause The Postal Dude to fire repeatedly. Yee-hah." — The machine gun's description in the manual
The machine gun was originally the only weapon capable of fully automatic fire in POSTAL 2.
The weapon can take quite a number of shots to drop someone, but the high accuracy compensates for this. Despite it being one of the more superior weapons in the game, it is probably the most common out of all of them and can be found in houses, rooftops, and various other places. The police armory is almost always full of machine guns.
In Enhanced Mode, the Machine Gun's secondary-fire causes it to shoot ricocheting scissors which can be very useful for quickly taking down armored enemies and bosses.
The machine gun reappears in Postal III, however it has been renamed to it's real-word name, the "M16". It functions as it did in the previous game (can be upgraded with cat silencer) except with added reload mechanics. Magazine holds 30 bullets, max in inventory is 300.
In addition to this, there is another Machine Gun known as the M-Gun. Based on the real world "M249", it is far more powerful than the M16 but far less accurate. It's magazine holds 100 bullets, max in inventory is 400.
- The machine gun in Postal seems to be an Beretta M12, in Postal 2, Apocalypse Weekend and Postal III it is a Colt M16A2/3(A2 rear sight). Meanwhile in Redux, it gets replaced with the Submachine Gun.
- The machine gun in the Postal 2 beta at E3 2002 was an M16A2 with an ACOG sight.
- In Postal, the machine gun's firing sound is similar (but not identical) to the sound used by pistols of Technicians in Command & Conquer: Red Alert. in Postal 2 Beta E3 2002, It uses a generic Chaingun sound effect. In the final version, it uses the sound Zillas use for their Uzis in Shadow Warrior (1997).
- The M-Gun in Postal III was originally based on the M60 and was seen from 2007 til' sometime in 2010. the weapon did not have a bullet box, so the chain/belt dangled freely via the use of jigglebones. the switch to an M249 seems to be a last minute decision made right before the release in 2011, as the M60 can still be seen in GC 2010 footage.