Special operations. The name says it all: specially trained individuals conducting highly specialized missions using a range of specialized hardware. Whether they are leading cavalry charges of freedom fighters or helping to yank foreign despots from their underground hiding places, U.S. special operations forces have at their disposal the most cutting-edge weaponry.
Looking toward the future, special operations planners are calling for a new-generation weapons system designated the Special Operations Forces (SOF) Combat Assault Rifle (SCAR). Envisioned as a family of weapons, SCAR will be developed in two primary configurations: SCAR-Light (SCAR-L, 5.56 x 45mm) and SCAR-Heavy (SCAR-H, 7.62 x 51mm), with SCAR-L leading the acquisition process. A characteristic of the follow-on SCAR-H model is the use of an Open Architecture design that will accommodate changing calibers from the standard NATO 7.62 x 51mm. The initial caliber change is projected as the 7.62 x 39mm used in the AK-47 and other international weapons series.
Barrett M82 The .50-cal. M82 series long-range sniper rifles entered service during Operation Desert Storm and have proved effective against material targets.
Both SCAR configurations will possess the capability for barrel modularity and thus will be available in the following variants: Standard, Close Quarters Combat and Sniper Variant. Maximum size for the SCAR-L is 29.9 in. (stock collapsed or folded)/33.6 in. (stock extended with standard barrel) with a maximum unloaded weight of 7.25 pounds. Size and weight goals for SCAR-H are 30.3 in. folded/40.2 in. extended with standard barrel, and no more than 9 pounds. Among its capabilities, the SCAR family will be compatible with all components of the SOPMOD kit.
Industry designers have recently unveiled several new weapon design concepts in response to the SCAR requirements. Knight’s Armament, for example, has traced a growth path from its current SR-25/Mk11 weapons to the SCAR-H design. The company has shown great flexibility in recent years, even producing prototypes for an SR-47 (Stoner Rifle) design that was externally identical to the M4 carbine but re-engineered to fire the AK-47 banana clip and 7.62 x 39mm ammo.
Barrett XM109 Firing a 25mm “cargo round,” the XM109 marks the boundary between sniper rifle and cannon.
“We’ve showed special operations representatives the Mk11 and then we showed them a Mk11 of a different lower receiver that had a collapsible buttstock,” explains David Lutz, Vice President of Military Marketing for Knight’s. “Then we took the upper receiver—which has a 20-in. barrel—off the new collapsible lower receiver and we pulled out what we call ‘The Battle Rifle,’ with either a 16-in. or 14.5-in. barrel. That now goes on the collapsible stock SR-25 lower receiver. As far as we’re concerned, we think this is certainly your ‘immediate term’ SCAR-Heavy.”
Meanwhile, special operations planners continue to support the immediate needs of special operations personnel in the field. For their part, the special operators are continuing to go wherever they are needed and do whatever needs to be done.
TEST FIRING THE XM8
Searching for downrange targets, I slid my index finger forward in the trigger guard, hitting the bolt catch release and chambering the first 5.56mm round. The ambidextrous thumb lever on both sides of the handgrip smoothed my lefthanded transition from safe, through semi, to full-automatic fire. The initial burst was directed at a torso target, and the weapon’s high sightline and innovative stock design provided heads-up assurance that the bulk of the bullets were plastering the cardboard victim.
PM was in the Nevada desert to test fire the newest addition to the Army’s small-arms arsenal, the XM8 lightweight carbine system.
“The XM8 is an experimental M8 carbine,” explained Jim Schatz, Manager, Military Programs, HK Defense. “XM8 is the Army designation for what the Army expects will be its new combat assault rifle system. If it is successful and if it’s fielded, the XM8 weapons system is intended to replace the M16/M4 family of weapons.”
Explaining the Army’s need for the new XM8 system, Schatz acknowledged that “the M16/M4 family of weapons have been around for 40 years and they continue to serve the military very well. We take nothing from the design of Gene Stoner. It’s brilliant. But there are certain requirements that the conventional Army has for a new assault rifle to reduce the training burden, to increase the service life, and to increase the reliability of that M16/M4 system.”
The XM8 employs a proven operating system that uses a pusher rod located above the barrel, pushed to the rear by a piston. When a round is fired, gas comes up into the cylinder, pushing a piston rod that strikes the bolt carrier and drives it to the rear.
“Once the piston comes about 6mm to the rear, all the excess gas, which you don’t need to operate the gun, goes out the front, out of the muzzle and out of the gas venthole. And all the carbon goes out of the muzzle with it,” Schatz said.
The operating system is one feature in a totally modular weapons design that Schatz likens to “a Lego set” in terms of its ease of assembling components and accessories.
The XM8 weapons system includes four major variants: Baseline Carbine, Compact Carbine, Sharpshooter and Automatic Rifleman. Automatic firing rates for all variants fall within 700 to 825 rounds per minute. Barrel lengths vary from 9 to 20 in. Firing the standard NATO M855 5.56mm bullet, muzzle velocities vary from 2400 fps (9-in. barrel) to 2700 fps (12.5-in. barrel) to 3000 fps (20-in. barrel).
Moving to the range, our own firing experience with multiple XM8 variant prototypes provided a new appreciation for the design features and inherent program lethality.
As these pages WENT to press, XM8 prototype testing continued through summer 2004 with the formal “decision to adopt” scheduled for September. A positive decision would lead to initial production early in 2005 with the first fielding later that year.
Read more: Weapons Of The Special Forces – Popular Mechanics
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