Special Operations Forces Combat Assault Rifle

Army, May 2006 by Gourley, Scott R

Selected U.S. military forces will soon receive enhanced individual combat capabilities in the form of a new family of assault rifles designated as the Special Operations Forces (SOF) Combat Assault Rifle (SCAR). As these pages go to press, the weapon system is in its final phase of development by FNH USA LLC, a subsidiary of FN Herstal, S.A., Belgium.

The SCAR weapon system streamlines the current joint service special operations family of rifles by replacing the existing M4A1 carbine, MK18 close quarter combat carbine, MK11 sniper security rifle, MK12 special purpose rifle, M14 rifle and two basic gas operated, rotating bolt weapons that can be configured to meet specific tactical requirements.

The SCAR effort emerged in early 2003, when U.S. Special Operations Command (USSOCOM) representatives began to conduct "sources sought" investigations for a new combat assault rifle capability. Initial industry conferences were held in August of that year, with comments received during that period feeding into operational requirements documentation and initial performance specifications.

Released in draft form late that year, the initial specifications called for procurement of a quantity of assault rifles in both "SCAR-Light" and "SCAR-Heavy" configurations.

After confirmation of the system performance specifications and final revisions to the requirements documentation, USSOCOM officially released the SCAR solicitation in January 2004. This was an extremely busy time in the small arms arena, with the Army extensively involved in testing its XM8 assault rifle program during this same period.

Contractors submitted prototype weapons to the Naval Surface Warfare Center (NSWC), Crane Division, in June 2004, with that prototype testing contributing to the subsequent source selection decision.

In November 2004, USSOCOM awarded an indefinite delivery indefinite quantity (IDIQ) contract for SCAR to FN Herstal, S.A. Company representatives emphasized that the award was made after the military conducted a full and open competition for 10 months starting in January 2004, noting, "The program provides the first 21st-century modular assault rifle designed and built from the ground up for the finest fighting forces in the world."

In fact, program sources at NSWC Crane point to operator involvement in the initial SCAR requirements generation process, including early market research with industry, operator involvement in early user assessment, and the assignment of several operators to the SCAR source selection panel.

FNH USA representatives echoed the government's emphasis on user participation in the weapon design effort, adding, "During the four-month period after a contract award, the SCAR program holds three joint design reviews with the FN team. These reviews keep FN Herstal, SOF operators, and NSWC Crane engaged in a continuous improvement process before delivery of the SCAR test units. USSOCOM component command/ user representatives, FN engineers representatives and program office personnel attend these joint reviews.

"The reviews afforded the SOF operators opportunities to review design concepts in real time with the use of rapid prototyping models. Interaction between the government team and the FN Herstal team proves to be invaluable. A single focus evolves throughout the process - to build a bridge between operational experience and engineering/design expertise and reduce risk before delivery of the SCAR test units."

The SCAR has been developed in two threshold configurations, a MK 16 SCAR-Light (SCAR-L, 5.56 x 45 mm) and a MK 17 SCAR-Heavy (SCAR-H, 7.62 x 51 mm).

Concurrent development efforts also include an enhanced grenade launcher module (EGLM).

Both light and heavy SCAR models are capable of either single shot or full automatic fire and feature barrel modularity that allows each model to be configured in three different variants: standard (S), close quarters combat (CQC) and sniper variant (SV). The SV can be a modular enhancement or a separate weapon. The barrel modularity can be accomplished by changing the complete upper receiver or simply the barrel.

With standard barrel configuration, the SCAR-L weighs 7.24 pounds (without magazine/with iron sights) with maximum length of 24.09 inches (stock folded) to 33 inches (stock extended). By comparison, the SCAR-H with standard barrel weighs 7.74 pounds (without magazine/with iron sights) with maximum length from 31.4 inches (stock folded) to 40.2 inches (stock extended).

Company program descriptions note that the SCAR-L is optimized for 5.56 x 45 mm while the SCAR-H provides an open architecture design to accommodate changing calibers from the standard 7.62 x 51 mm (NATO). The initial caliber change is projected to be the 7.62 x 39 mm (used in the AK-47).

The ergonomie and parts commonality between the SCAR-L and H will be maximized in the creation of an entire family of SCAR weapons.

In addition to the barrel modularity noted above, common features inelude short stroke gas piston operation, the enhanced folding stock, 550 rounds per minute rate of fire, and ergonomic compatibility.