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.
Scott Gourley
ASSAULT RIFLES

Colt M4A1 SOPMOD Special operations forces can personalize their fully automatic M4A1s with a broad range of SOPMOD accessories.
Few weapons provide today's special "operators" with the tactical flexibility offered by the M16/M4 series' Special Operations Peculiar Modification (SOPMOD) hardware. Under the coordination of the SOPMOD Program Management Office at the Naval Surface Warfare Center in Crane, Ind., the SOPMOD is a kit concept designed to provide standardized, versatile weapons accessories to meet needs across special operations mission scenarios. Individual accessories are selected for the SOPMOD kit based on their contribution toward increasing operator survivability and lethality by enhanced weapon performance, target acquisition, signature suppression and fire control.The SOPMOD concept is based around the M4A1, the special operations variant of the Colt 5.56 x 45mm M4 Carbine, a versatile weapons system with a sliding buttstock and 14.5-in. barrel (the special operations A1 version is capable of fully automatic fire). When equipped with multiple accessory-mounting surfaces, the M4A1 SOPMOD allows the special operator to tailor his weapon to specific mission requirements.

Marine Corps M14 DMR The enhanced 7.62 x 51mm DMR re-entered service during Operation Enduring Freedom.
Examples of the components contained in the current SOPMOD kit include: 4X Day Scope, Reflex Sight, Rail Interface System (MIL-STD 1913), Vertical Forward Handgrip, Quick Attach/Detach 40mm M203 Grenade Launcher Mount and Modified Leaf Sight, Quick Attach/Detach Suppressor, Infrared Laser Pointer/Illuminator, Visible Laser, Visible Bright Light (9-volt flashlight), Backup Iron Sight, Combat Sling, Sloping Cheek Weld Stock, Mini Night Vision Sight, Universal Pocket-scope Mount, 9-in. M203 Grenade Launcher Barrel, and Kit Carrying/Storage Case.
In addition to these components, there are rumors of a 10.5-in. barrel "upper receiver" component option as well as ongoing plans to add an enhanced grenade launcher module (EGLM) to replace the aging bottom-loading M203 attachment. One example of an available system that could meet EGLM requirements is the AG36 side-loading 40mm grenade launcher developed by Heckler & Koch.

Knight's Armament Stoner Rifles The Army Rangers' SR-25 and the Navy SEALs' Mk11Mod0 are adaptations of the same Gene Stoner rifle design.
REACH OUT
While 5.56 x 45mm weapon designs provide a range of ballistics options, an increasing number of special operations programs are returning to the 7.62 x 51mm cartridge for extended-range engagements. Examples of this trend include the Marines' fielding of highly modified M14s, called Designated Marksman Rifles (DMRs), to units that have been operating in Afghanistan since early 2002. Also, the Army fielded M14s to snipers within the new Stryker Brigade Combat Team immediately prior to that unit's Iraq deployment in the fall of 2003.
Within the pure special operations world, the 7.62 x 51mm has been fielded as the U.S. Army Ranger Regiment's SR-25 (Stoner Rifle) as well as the Navy SEALs' new Mk11Mod0 sniper rifle (deliveries were completed in 2002). Both of the weapons are manufactured by Knight's Armament and are nearly identical except for the Mk11 designator on the Navy's 365 systems.
OLD FAITHFUL
For seriously reaching out and touching something, the current king within U.S. special operations is the .50-cal. M82 series from Barrett Firearms Manufacturing. Tactically employed in special missions during Operation Desert Storm, the original civilian version M82 series has most recently been joined by the M82A1M/M107.
With a length of 57 in. and a rifle weight of 30 pounds, the M107 is hardly optimized for close-quarter combat. However, with its 10-shot detachable box magazine of .50-cal. lethality, the weapon is in such demand that the Army has accelerated wider fielding to its combat units with the "XM" experimental designator still in place. Minor differences between the M107 and earlier civilian models include forks on the folding bipod (the civilian version has a flat bottom bipod) and a new plastic rear grip for comfort in cold weather.
HIT HARD
For some special operations missions, size definitely does matter. And .50-cal. won't do the job. For those situations, Barrett Firearms has developed the XM109 25mm payload rifle. With an overall length of 46 in. and a rifle weight of 33.2 pounds, the XM109 incorporates a new upper receiver onto the M82A1 .50-cal. rifle together with the necessary modifications to hold a 5-round box magazine of 25mm "cargo rounds."
According to Bob Gates, who works on the program at Barrett Firearms, the XM109 is currently under a government contract "for refinement of some changes that they want made to the gun.
Recent activities have reportedly focused on designs to reduce recoil to less than 60 ft.-lb. In addition, the gun manufacturer has been providing engineering support to the effort to refine a 25mm Armor Penetrator round now under development by General Dynamics.
Noting that the program was briefed to U.S. Special Operations Command in December 2003, Gates adds, "The program is on track for us to field six prototype XM109s in August 2004 to the spec ops community, and those weapons will be equipped with the Barrett Digital Ranging Optical Sight."
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