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One of the more popular weapons in Iraq, for those that can afford it, is the Glock 18C 9mm pistol. This one looks just like the widely used Glock 17 pistol, but with one major difference, the Glock 18 can fire full auto (1200 rounds a minute). Since the Glock 18 magazine only holds 17 rounds, this means you can empty it in less than second. However, you can also fire two or three short bursts instead, once you get used to firing a fully automatic pistol. A selector switch on the pistol allows you to switch between standard semiauto, and full auto. There is also a special 33 round magazine for the Glock 18. Loaded with a standard 17 round magazine, the Glock 18 weighs about two pounds. The pistol is 7.3 inches long, with a 4.5 inch barrel. The current model, Glock 18C was developed in the late 1990s, for military and police use. An earlier version, introduced in 1986, had a lower rate of fire (350 rounds a minute).

Operations in tight spaces, like hallways or homes, often make the use of a submachinegun, or assault rifle, awkward. But the Glock 18, which is so well designed that it can be accurately fired, full auto,  with one hand, provides the instant firepower that can be a lifesaver in such situations. The Glock 18 retails for a thousand dollars, and is particularly popular with VIP security personnel. Nothing stops an assassination attempt faster than a hail of 9mm bullets.

Its also possible to buy an FSSG (Fire Selector System for Glock Pistols), which converts any Glock pistol to a full auto weapon. The FSSG is made of reinforced glass filled polymer and weighs less than an ounce. 

Video of the Glock 18C in action.