The MP5 was developed in the 1960s by a group of engineers from the West German arms manufacturer Heckler & Koch GmbH (HK). The company, motivated by the success of the Heckler & Koch G3 rifle developed a group of small arms consisting of four types of firearms (all based on the G3 design layout), where the first type was chambered in 7.62 x 51 mm NATO, the second – using the 7.62 x 39 mm round, third – the intermediate 5.56 x 45 mm NATO caliber and the fourth type – chambering the 9 x 19 mm Parabellum pistol cartridge. The MP5 (short for Maschinenpistole 5) was created within the fourth group of firearms, initially known as the HK54.
The SMG is one of the most powerful submachine guns in the GTA series, with devastating effects to both the player and non-player targets alike. It is arguably a better substitute for the Micro Uzi and Micro-SMG, holding a better rate of fire and more damage per round. However, like the Micro-SMG, the MP5 has the disadvantage of disallowing the player from discharging the weapon while running, allowing the player to only stand or stride while taking aim or shooting. Since its inception in GTA Vice City, the weapon is favored by both the FBI (and GTA IV's FIB) and GTA IV's NOOSE tactical units as a weapon of choice. All renditions of the MP5 hold 30 rounds per magazine.
Each MP5 rendition has a variant in the GTA games. GTA Vice City and San Andreas feature an MP5A3, and GTA Liberty City Stories features the MP5K which looks a little lengthier than the other renditions. In Vice City Stories, the SP89 (a civilian version of the MP5K) makes an appearance, but the model also contains parts of the MP5A3, MP5K and MP5SD. In GTA IV, the MP5 is heavily modified and resembles the look of an MP10. In GTA Chinatown Wars the MP5 is called the SMG, just like any other rendition.
The SMG can be purchased at the back-alley gun shops for $2500 and each additional magazine costs $150. It can be purchased from Little Jacob for $1750 and each additional magazine will cost $20. It is basically the most used weapon on multiplayer and a good weapon for single player also. It is a 2 hit kill with head-shots on single player and multiplayer. It has about double the range of an Uzi and almost the range of an AK, but not as much range as an M4. This weapon is good for drive-bys and car chases as it has an high rate of fire and a 30 round magazine, but the Uzi is more suited for that purpose and this gun is more suited for attacking on the ground.
Schottler - Can be found on an air-conditioning duct-work in an alley between Boone St and Dillon St. This pickup isn't so tricky to get to: walk the alley opposite Jacob's home just to the dead end, jump to the left edge. you can't pull onto the roof near the roof windows so move along this edge left then pull up. It is where the mission Jamaican Heat takes place
Acter Industrial Park - Can be found on the seventh floor of an observation platform of a RON Oil refinery on the southern side of the island. This is a particularly long way to go to get this weapon, however, and is not recommended.
The SP89 is anachronistic to Grand Theft Auto: Vice City Stories, which takes place in 1984, while this variant of the MP5 was not made until 1989. In game it is fully-automatic, while in real life it is semi-automatic. However, it may be illegally custom converted to fully-automatic, as its much easier than to obtain a civilian version than a normal version.
A shorter version of the weapon, the MP5-K, was cut from Grand Theft Auto: Vice City. Model and textures for the weapon still remain in the game files (mpfshrt.dff and mpfshrt.txd). The weapon can also be seen in the intro of the game, being used by one of the men who ambush the drug deal.