Two years after completing field testing, the new American assault rifle, SCAR, has been issued to a battalion of U.S. Army Rangers, who are headed for Afghanistan. SCAR (Special operations forces Combat Assault Rifle) was a SOCOM (Special Operations Command) effort to develop a new assault rifle that had some of the characteristics of the (now abandoned) U.S. Army XM-8 rifle. SOCOM had the money, and authority to develop their own weapons. And SCAR is mainly for use by SOCOM troops.
SOCOM wanted a weapon that did everything the XM-8 did, and a little more. Back in 2003, SOCOM asked rifle manufacturers to submit proposals, and FN (a Belgian firm) came up with the best ideas. One advantage FN has was its ability to quickly implement requests for design changes. FNs rapid prototyping shop was often able to turn out a new part in hours. This, and FNs long history of good weapons design, gave them the edge. SCAR has a more reliable short-stroke, gas piston operating system, and a floating barrel for better accuracy, plus several other improvements over the current M-4/M-16.
There are two basic models of the weapon. The 5.56mm SCAR-L weighs 7.7 pounds (empty), while the 7.62mm SCAR-H weighs 8.5 pounds (empty). A 30 round 5.56mm magazine weighs a little under a pound, while a 20 round magazine of 7.62mm ammo weighs a little over a pound. Special sights can weigh a pound or two, so a fully loaded SCAR won't weigh much more than ten pounds. FN also came up with a grenade launcher for SCAR.
Both models operate the same way, and have many interchangeable parts. SCAR-L is basically a replacement for the M4, which was designed (with a shorter barrel) as a close combat version of the M16. The SCAR-H will replace the M14, a 1950s era 7.62mm weapon (a replacement for the World War II M1) that is still favored for long range and sniper work. The SCAR design is the result of much feedback from the field. For example, the rate of fire was lowered to 600 RPM (rounds per minute) from the 800 typical with the M14 and M16. This makes SCAR easier to hold on target when firing full auto.
SCAR-H can be quickly converted to fire AK-47 ammo (the 7.62x39 round) with a change out of the barrel and receiver. Both models can be fitted with a longer and heavier sniper barrel. Thus this ability to quickly change the barrel length enables the SOCOM to equip their troops with the specific weapon they need. SCAR is also built to be more rugged than the M-16. The barrel is good for some 36,000 rounds, twice as many as the M-16. Barrels may be switched by users without special tools. Both models of SCAR take all the special sights and other accessories SOCOM troops favor. SCAR is meant to be easily modified and personalized for each user. Its expected that SOCOM experience with SCAR will influence the next generation of U.S. Army and Marine Corps small arms.