The SM-9 is a machine pistol of Guatemalan origin and manufactured by Cellini-Dunn. It is blowback operated, firing from an open bolt and fed from 36 rounds magazine inserted in the grip. The layout of the receiver is somewhat simpler to that of a Sten with its internal components light in weight enabling a very high rate of fire. Its forward pistol grip can hold a spare magazine as well as handling the weapon when firing.
The SM-9 is a submachine gun which can fire in semi or full automatic. The SM-9 is provided with a front sear, a front trigger and a rear sear/trigger in a construction which allows the operator to instantly change between the semi and full automatic mode without a selector switch, even when firing. Other features include capability for ambidextrous operation, the use of two magazines each located in a foregrip and an improved muzzle brake configuration. In addition, an improved ejector and magazine catch assembly are provided. The SM-9 uses fewer moving parts so as to require no pins or screws for the trigger, sear, bolt guide or bolt stop.
The SM-9 provides an improved automatic firearm having features which include instinctive fire control, a layout that comes with a unique arrangement of front sear and trigger with a rear sear/trigger to allow the operator to instantly change between the semi and fully automatic mode without a selector switch, even while firing. The ergonomics of the SM-9 is totally ambidextrous for a right or left handed user has complete access to all of the weapon operating controls. This feature has been achieved by placing the charging handle and both magazine catches on the longitudinal center axis and constructing the foregrip to rotate up to 90° in either direction. Such a construction also provides a more comfortable foregrip and permits the weapon to be fired blind behind a right or left hand corner while maintaining positive control. Also, in less than one minute, the front hand grip can be removed without tools, transforming the firearm into a semi or fully automatic pistol which is easily concealed for executive or dignitary protection.
The SM-9, employs a unique merger of fewer moving parts, requires no pins or screws for the trigger, sear, bolt guide or bolt stop, thus resulting in fewer operational problems. Due to the particular construction of the SM-9, even if the front sear, front trigger and charging handle were all to be damaged so as to require removal, it would still be possible to fire the weapon, fully controlled, in full automatic mode, with the operator using a finger to cock the bolt, after which it can fire with the rear trigger. In addition, the barrel, barrel nut and muzzle brake are provided in the form of an integral one-piece assembly that allows instant barrel replacement. Thus the entire weapon can be field stripped in a short period of time without the use of tools.
The SM-9 comes with dual magazines, with the active magazine insert in the pistol grip which provides firm support for the magazine. A second magazine is stored in the foregrip, allowing rapid magazine exchanges, especially at night, using the principle of "hand finds hand". In one embodiment, each magazine contains 32 rounds, thus providing an unprecedented amount of ammunition within the weapon. The magazines can be loaded by hand without the inconvenience of speed loaders.
The futuristic appearance of the SM-9 is the result of specific construction features which provide functional superiority. Thus the tubular receiver, flush sides, rounded upper body and built-in heat sinks of the firearm all contribute to improved operation. In addition, the smooth sleek construction of the SM-9 results in no protruding parts which can snag fabric or vegetation. The short overall length of the firearm was obtained by telescoping the bolt around the barrel. The light weight of the SM-9, which in one embodiment is only 4.3 pounds (1.95 kg) without magazines, makes it one of the lightest weapons of its type. The SM-9 produces a muzzle velocity of 1280 fps (390 mps) using 9x19mm parabellum ammunition, firing at a rate of 1200 rpm. Also to note, the front sear of the SM-9 is stronger and highly durable than any known in use today.