Colt Model 635 (Colt 9mm SMG)

History

Colt would introduce the AR-15/M16 style gun, which is somewhat of a surprise, that holds the ubiquitous 9x19mm Parabellum pistol cartridge. The cartridge was in use for decades prior to the 1980s and was used in both world wars, while becoming the cartridge of choice for many semi-automatic pistols and submachine guns.

The Colt entered the Type 635 (called "SMG 9mm NATO" by NATO), which, as expected, was loaded with 9mm bullets and fired through a closed recoil action (as opposed to the direct impact gas in the M16) to become a-bolt system.

The Model 635 - commonly referred to as the "Colt 9mm submachine gun" - retains the general design lines of the classic US M16 assault rifle (its own design is based on the AR-15). It shares some characteristics with the early Vietnam-era Colt "Commando" assault carbine.

For compactness, a telescoping stock was installed, reducing the overall length of the gun from 29 inches to a more manageable 25.5 inches as needed. The M16-style fire control system is retained, meaning operators already familiar with the larger cousin can easily adapt to manage the smaller product.

One of the more unique design elements of the Type 635 is the magazine, which is slimmer and borrowed from the Israeli UZI SMG design. To accommodate these new magazines in the M16-style feed, special internal modifications were introduced.

The Model 635 is fed from a 20- or 32-round straight, detachable magazine and has a standard barrel length of 10.5 inches.

Accuracy and familiarity proved the Model 635's selling point, but the system didn't find many takers. Militarily, only the U.S. Marine Corps, the Malaysian and Argentine Army have adopted this type, the Bangladeshi and Indian Special Police Forces are the other operators. On the ground, the U.S.

Marshals Service, the U.S. Diplomatic Security Service (DSS), and the Drug Enforcement Administration (DEA) saw enough benefits in the design to include it on their lists.

The Type 639 became a related variant with a select-fire trigger group that included triple burst capability, but lacked the fully automatic mode of the original Type 635. The Type 633 appeared with a shorter 7" barrel assembly for improved compactness as well as a simplified front sighting - these continued to serve the DEA.

Specification

Roles

Dimensions

Performance

Changes