- Not to be confused with the Colt Model 703, a Colt designation for a M16A2 export model with the same name.
The Colt Model 703 is a prototype assault rifle derived from the AR-15.
History[edit | edit source]
In 1967, during the Vietnam War, a special subcommittee of the United States House Armed Services Committee, headed by Senator Richard H. Ichord, published a report on the M16 rifle program. The report identified the failures of the early M16 rifle in combat. In response, Colt developed the Model 703 as an improved version of the M16, featuring an AK-styled long stroke piston operation.
Two prototypes of the Model 703 were made, and a report on the prototypes was published by Colt in May 1969, titled Colt's Automatic Rifle Model 703. In the end, the Model 703 was not adopted by the United States military, and their designations were later recycled by Colt for a different gun.
The two prototypes are now in the private collection of Knight's Armament Company founder C. Reed Knight, and are currently stored at the Knight's Firearm Museum.
Design[edit | edit source]
The Model 703 is a derivative of the AR-15 design, featuring an AK-styled long stroke piston operation, one of the first AR-15 derivatives to have such a feature. The lower receiver remained largely the same, while a completely new upper receiver operated by an external piston was made for the Model 703.
The bolt carrier has the long stroke operating rod pinned to its top, while two grooves on its side fitted into two slots on the upper receiver, acting as guides to the movement of the bolt carrier group. The gas system utilizes a gas regulator, allowing the user to adjust it to fit their needs.
The Model 703 prototype also incorporated a four-position selector switch, adding a 2 or 3 round burst fire mode in addition to the standard safe, auto, and semi-auto modes. The handguard was also redesigned, making disassembly easier, and a cleaning kit trap was added to the buttstock, a feature that would later be incorporated into the M16A1.