“If we describe an all-volunteer force of warriors who share the core values of honor, courage and commitment and who are renowned for their professionalism, expertise, innovation, and superior physical fitness, you would be hard-pressed to decide whether we described Marines or SOF (Special Operations Force) operators. We found plenty of common ground to build on, but … the question at the heart of the issue is what is a MarSOF warrior” MARSOC Information paper

It defies logic that United States Special Operations Command did not include the Marine Corps until a little over four years ago. All the more so because the Corps is arguably the most nimble, aggressive and experienced component of the U.S. Armed Forces in the dirty and demanding business of fighting “small wars” in remote corners of the world.

Marines, also colorfully known as Leathernecks and Devil Dogs, are proud to be major players in more conventional aspects of the Global War on Terrorism, launched by the U.S. and allies following the murder of thousands of innocent Americans in horrific suicide attacks by Islamic extremists on September 11, 2001. But, until recently, SPECOPS missions against freedom’s many foes have been the exclusive domain of soldiers, sailors and airmen.

Lucky for USSOCOM – and not so lucky for bad guys around the globe – the puzzling omission of the Corps, with a long and rich history of success in expeditionary warfare and home to hard-charging, superbly trained Marine Force Recon, was corrected by President George W. Bush.

In October 2005, Donald H. Rumsfeld, the Bush administration’s Secretary of Defense, directed the formation of a 2,500 man Marine Component to serve with USSOCOM. Four months later, on February 24, 2006 Marine Corps Special Operations Command, led by Major General Dennis Hejlik, was formally activated at Camp Lejeune, NC.

Fast, Steep Climb

MARSOC immediately moved forward at double time with a small but highly motivated headquarters staff, drawn primarily from personnel who became available following deactivation of the 4th Marine Expeditionary Brigade (Anti-Terrorism). Urgent demands of the GWOT necessitated building force structure and conducting initial operations at the same time, which one insider said was like “painting a car while driving 50 miles per hour.”

The Foreign Military Training Unit (FMTU) was the first fully operational element, tasked with hands-on training as well as conduct of Foreign Internal Defense missions to assist friendly nations struggling against terrorist networks.

FMTU was fortunate to have quickly attracted a heavy concentration of experienced and capable NCOs with proficiency in relevant foreign languages and ability to effectively teach a wide range of practical military skills. It grew to two companies, began taking on some Unconventional Warfare/Foreign Internal Defense taskings, and its teams regularly deployed to train and advise several developing countries engaged in counter-terrorism operations.

Hejlik, appearing before a congressional committee in January 2007, noted with pride a particular success that followed MARSOC assistance to the African nation of Chad. A major assault the previous year by Islamist rebel forces advancing on the capitol was stopped and pushed back, he said, by two battalions of the Chadian military that had been trained by FMTU teams.

With FMTU’s expanding and evolving role came a name change to Marine Special Operations Advisor Group, and it has most recently restructured to become the Marine Special Operations Regiment’s Headquarters and its 3rd Marine Special Operations Battalion, both close to MARSOC’s flagpole aboard Camp Lejeune.

Door Kickers

The Corps’ Force Reconnaissance companies – repeatedly proven effective for the most demanding missions launched from land, sea and air – were essential assets in the fast and steep climb to full operational capability. In the months after the activation of MARSOC, the structure and personnel of both 1st and 2nd Force Reconnaissance Company transferred to MARSOC to form the 1st and 2nd Marine Special Operations Battalions. Both MSOBs retained their traditional home bases, with the 1st at Camp Pendleton, California, and the 2nd at Lejeune.

In the beginning, all operators in these “tip of the spear” companies already held the 0321 Reconnaissance Man MOS (military occupational specialty), designating them as elite Recon Marines. The current training pipeline for what are now called Critical Skills Operators (CSO) accepts experienced Marines and Sailors from any MOS who can meet a long and serious list of requirements. Graduates of the Individual Training Course may eventually receive an Additional Skill Identifier signifying qualification as a CSO, but for the time being a special code on their training record notes this achievement.

Marine Special Operations Teams are the basic building block for highly flexible and tailorable employment in a wide array of taskings. Marine Special Operations Company structure calls for four Teams, each usually consisting of 12 Marines plus two Navy Corpsman, all qualified CSOs with a common set of capabilities and each having additional special skills.

Teams usually deploy as part of a task-organized MSOC that is augmented by detachments from Marine Special Operations Support Group. MSOSG specialists provide necessary skill sets such as EOD (explosive ordnance disposal), K-9 working dogs, targeted intelligence, sophisticated communications, and others.

Operational tempo for these first two hard-charging battalions – colorfully known as “door kickers” for the Direct Action part of their mission capabilities – started fast and quickly grew. The first Marine Special Operations Company stood up in June 2006 and deployed to GWOT in December with 26th Marine Expeditionary Unit (Special Operations Capable). Their role was similar to the MEU’s Maritime Special Purpose Force, well equipped and manned with specialists in the conduct of maritime interdiction, deep recon, direct action, and close quarter battle.

Security requirements necessarily cloud details of most subsequent missions but cross-referencing various sources reveals the number of operational activities rapidly increasing each year, most notably in Iraq and Afghanistan. By March 2009, the third anniversary of MARSOC, Marine Special Operators were regularly deploying for dozens of missions in support of Operations Enduring Freedom Afghanistan, Philippines, Horn of Africa, and Trans Sahara. The number and variety of deployments continues to grow and task forces are operating in at least four of USASOC’s Theater commands including Central, Europe, Pacific, and South.

Essential Training and Support

Providing intensively trained operators to round out all twelve “door kicker” companies in the regiment’s three battalions is the responsibility of the Marine Special Operations School. Building on the structure and field work of 1st and 2nd Special Missions Training Branch, MSOS was activated in June 2007 at Camp Lejeune.

Informally known as the “schoolhouse,” it is tasked to screen, assess select, train, and certify Marine Special Operations Forces. It also has responsibility for doctrine development and serves as the proponent for evaluation of weapons and optics used throughout MARSOC.

In October 2008, all Marines seeking to become MARSOF Operators began attending Individual Training Course, an in-depth training program that covers required culture, technical, and tactical skills. The grueling seven month program of instruction gives all operators the same baseline training.

After graduation, most report to the Regiment where they will undergo further specialized training based on the unit that they are assigned to. Others will first go on to more advanced training in language and other skills like Airborne, SCUBA, and emergency medical care.

(Editor’s Note: Part two of this series will take a close look at how MARSOC’s Critical Special Operators are trained in high-stakes weapons handling and employment, as well as other critical combat skills.)

Marine Special Operations Support Group provides combat support and combat service support to MARSOC units. A Logistics Company handles food, fuel, ammunition, heavy transport, maintenance, and other essentials. A Support Company provides communications, K-9 and control elements for external sources of heavy firepower. Plans call for a full spectrum of intelligence capabilities to dramatically expand with formation of a dedicated Intel Battalion.

With its organizational structure in place and the number of assigned personnel trained and performing at acceptable level, MARSOC announced in October 2008 that it had achieved the remarkable feat of full operational capability.

Worldwide Reach

“In all fighting, the direct method may be used for joining battle, but indirect methods will be needed to secure victory.” Sun Tzu, THE ART OF WAR, ca. 500 BC

As directed by the Commander of USSOCOM, MARSOC deploys task organized, scalable, and responsive U.S. Marine Corps special operations forces worldwide in support of combatant commanders and other agencies. While MARSOC’s contributions are not dissimilar to some in other components of USSOCOM, they are strongly influenced by the unique culture and character of the Marine Corps:

• Foreign Internal Defense (FID) – Providing training and other assistance to foreign governments and their militaries to enable the foreign government to provide for its country’s national security.
• Counterinsurgency (COIN) – Those military, paramilitary, political, economic, psychological and civic actions taken by a government to defeat insurgency.
• Security Force Assistance (SFA) – Operations, actions or activities that contribute to unified action to support the development of the capacity and capability of foreign security forces and their supporting institutions. Also, the augmentation of a foreign security force or its supporting institution in order to facilitate the achievement of specific operational objectives shared with the U.S. government.
• Special Reconnaissance (SR) – Acquiring information concerning the capabilities, intentions, and activities of an enemy.
• Direct Action (DA) – Short-duration strikes and other small-scale offensive actions taken to seize, destroy, capture, recover or inflict damage in denied areas.
• Counter-Narco Terrorism (CNT) – Military capabilities that support domestic law enforcement agencies and foreign security forces to counter activities that aid, benefit from, or are related to drug trafficking.
• Additionally, MARSOC is developing capabilities in Unconventional Warfare (UW), Counter Terrorism (CT), and Information Operations (IO).

Building future capabilities

At the end of February, 2010, MARSOC’s roster listed 1,965 Marines, 180 Sailors, and 124 civilians. This puts the command at better than 90 percent of the 2,500 personnel currently authorized. Intensified recruiting efforts within active and reserve units of the Marine Corps and Navy are underway to fill specialized MOSs in the Support Group, as well as to encourage those with the potential to become Critical Skills Operators. There is talk of an increase in the number of Individual Training Course classes to boost quantity without diminishing quality.

Under Major General Paul Lefebvre, MARSOC’s third commander, who succeeded Major General Mastin M. Robeson in November 2009, MARSOC continues reshaping and reorganizing to better balance the capabilities of MARSOF and its operator/support ratio. Standardization of the three MSOBs under the Regiment, establishment of an Intelligence Battalion and other important initiatives in the Support Group, are designed to enable a long term relevant special operations force with greater agility and self sufficiency in the execution of direct and indirect missions.

Under Construction

Evidence of some $700 million in construction projects underway was inescapable during our visit in early 2010 to MARSOC at its central complex at Lejeune’s historic Stone Bay. While an imposingly large and modern looking headquarters building, opened for business in November 2009, stood tall but alone among capacious parking lots and acres of recently-cleared land, construction crews were hard at work in several nearby locations.

A master plan drawing shows a sprawling campus with numerous specialized ranges, shoothouses, tactical training areas, armories, logistics centers, motor pools, helipads, and much more. These, along with the excellent infrastructure and air/land/sea geographical advantages of MCB Camp Lejeune and Marine Corps Air Station New River, as well as tactical and strategic airlift assets at nearby Pope Air Force Base, provide most everything needed for training, launching and sustaining global-reach special operations.

Marine Corps Warriors

“The MARSOC Marine secures victory by going forth with our allies to fight the next battle before it begins.” (MARSOC recruiting video)

So, what is a MarSOF warrior? How does he differ from other Marines?

Answers to these fundamental questions were provided by MARSOC in a particularly detailed information paper that was published in the Marine Corps Gazette’s August 2008 issue and excerpted here with MCG permission:

Whether deployed as part of a joint special operations task force, a Marine MSOC or MSOT, or as a task-organized enabler detachment of just a few Marines and corpsmen, our silent warriors are strategic and tactical force multipliers. They must be able to operate in austere environments far from the combat service support generally available to Marine Corps forces.

For example, a key distinction between MSOCs and traditional rifle companies is that MSOCs deploy to an area of operations in order to find, plan, and execute missions independently rather than to conduct a preplanned mission. Such missions can range from direct action and special reconnaissance one day to foreign internal defense or unconventional warfare the next based on intelligence gathered and opportunities identified. This does not require a better Marine, but it does require a Marine with a unique combination of skills, experience, traits, and specialized training.

To succeed at the range of specialized missions they will conduct, MarSOF Marines and corpsmen must be multilingual, compassionate, determined, mature, team oriented, culturally aware, physically fit, capable, disciplined, independent, experienced, and mentally fit. Many of these qualities are developed during initial Marine Corps training; others are honed during deployments in Iraq, Afghanistan, and other areas of operations throughout the GWOT.

Learn More

MARSOC has an excellent website, with information on all aspects of this vital “tip of the spear” component at www.marsoc.usmc.mil.

Up Next

SAR visits MARSOC’s “schoolhouse” for a look at special operations weapons training. Our report includes conversations with some of the battle-hardened Marine NCOs who have been brought in from muddy-boots operational deployments. These men have a critical role as Instructors in the Individual Training Course and some follow-on Advanced coursework. Don’t miss it!

(SAR extends special thanks to MARSOC’s Public Affairs Office for exceptional assistance in arranging interviews and photo opportunities during our visit, then following up with much additional information and graphic elements.)

The SOPMOD (Special Operations Peculiar MODification) program was initiated by USSOCOM (United States Special Operation Command) and implemented by Naval Special Warfare Center, Crane Division, Crane Indiana, in the mid-1990s. SOPMOD set forth the requirements for a new family of weapons for SOCOM use that would be standard for all branches. This would include enhancements of the M4A1 carbines, rail adaptation systems, enhanced versions of the M16 series rifle, optics that include thermal, night vision, video module, range finder and integrated pointer-illuminator. In addition to optics would be silencer/ suppressors, muzzle brakes, bayonet and shot counter.

Part of the SOPMOD requirement was for a CQBR or Close Quarters Combat Receiver. It was to be between 10 to 12 inches and fit on the standard M4A1 lower receiver.

The CQBR
(Close Quarter Battle Receiver)
NSN 1005-01-498-1913

The CQBR receiver was first produced at Crane. The barrel started out life as a standard Colt M4 14.5 inch barrel. The gunsmiths at Crane would cut the barrel down to 10.5 inches, re-thread the muzzle and modify the gas port. Development of the CQBR barrel was assisted greatly by Karl Lewis, President of Lewis Machine and Tool (LMT). Then, a Knight Armament Company (KAC) RIS (Rail Interface System) and a flash suppressor/ quick detachment for the KAC silencer were added. The back-up rear sight chosen was one manufactured by Lewis Machine and Tool.

Due to the short 10.5 inch barrel, the CQBR receiver remains relatively cool even when firing at a faster rate of fire. The complete Colt manufactured Mk18 Mod O carbine. A standard government issue “Property of U.S. Govt M4A1” lower receiver with the six position LMT stock assembly mounted with the CQBR (Close Quarter Battle Receiver) consisting of the Lewis Machine and Tool back-up sight and SOPMOD stock with. Knight’s Armament RAS with rail protectors, vertical pistol grip and compensator (for use with KAC quick detach suppressor). Owing to the short barrel, a significant amount of powder burns after it leaves the barrel and with this decrease in temperature, and additional modifications, the CQBR carbine will have an extended barrel life over the standard M4A1 carbine 14.5 inch barrel.

As previously stated, the original 10.5 inch barrel was modified by the gunsmiths at Crane. Lewis Machine and Tool had also produced some 10.5 inch barrels. Colt got together with Crane and told them that rather than Crane go through the efforts of modifying the barrels of M4 carbines, Colt could just make the barrels to Crane’s specifications: which they eventually did. This made it simpler for Crane to have Colt barrels due to the fact Colt is the sole manufacturer of the M4 carbine and government inspectors were already present in their facility. The barrels would be made to the same manufacturing specifications as their standard GI M4 barrel. At around this time, the specification was changed for the barrel length. The new specification called for a 10.3 inch barrel instead of 10.5 inches. It was found that 10.3 inches was the shortest the barrel could be for installing the KAC sound suppressor. This is the configuration Colt is producing today.

Currently, Colt Defense manufactures the complete CQBR upper receivers and barrels. They are 10.3 inch light contoured barrels with a chrome lined bore and chamber with the standard 1 turn in 7 inch twist. The M4/M16A4 “F” front sight base is used to properly align the front sight with the rear. They come from Colt as per specification with the Knight Armament Company RIS as well as RAS (Rail Adapter System) as well as the KAC flash suppressors which are for use with their QD sound suppressor. The bolts provided by Colt have the black extractor buffer, heavy gold extractor spring and the rubber O-ring to enhance extraction force. As per military specification, the bolts are proof tested with a 70,000 psi proof cartridge and then Magnafluxed to check for stress fractures in the metal. According to Colt, there are several Bills of Materials for the Mk18 Mod 0. The back-up rear sights are provided by SOCOM to Colt. Normally, the provided sights are the Lewis Machine and Tool back-up sights, however; others may be supplied as well.

The Mk18 Mod 0
NSN 1005-01-527-2288
With the acceptance of the CQBR receiver, the complete weapon was type classified as the Mk18 Mod 0. The U.S. Navy/SOCOM has large stocks of obsolete M16A1 rifles that were in the navy arsenals. The M16A1 rifles were used as the host weapons for the CQBR upper receiver. The standard M16A1 rifle upperreceiver was replaced with the CQBR upper receiver. The original bolt carrier group from the M16A1 was used. Some of the original bolts were upgraded with the SOPMOD Reliability Kit including a new ejector spring that is much stronger and speeds up the ejection of the fired cartridge case. The three gas rings were replaced with a single McFarland gas ring and there was a rubber O-ring placed around the extractor spring increasing the extraction force by a factor of 4.

The lower receivers from the M16A1 rifles were modified for use with the CQBR upper receiver. The complete fixed stock/buffer assembly was removed and replaced with a telescopic stock assembly. The receiver extension plate was replaced with a 1-point sling adapter. The stock chosen was the SOPMOD stock assembly manufactured by Lewis Machine and Tool. This stock has a dual battery compartment for storage of batteries for optics. The profile of the LMT stock is triangular and is very similar to the Colt Advanced Combat Rifle stock. The receiver extension has six positions rather than the standard four of the typical GI Colt M4. Many weapons had disconnector springs replaced with the stronger carbine spring as well. However, many different stock assemblies may be seen on MK18s, although many are not “officially” authorized.

Colt provides both CQBR upper receivers as well as complete firearms. The complete firearms have CQBR upper placed on new Colt “Property of U.S. Government” marked M4A1 lower receivers. The SOPMOD stock is provided.

There is no standard MK18 configuration and the configurations mentioned in this article are the most common found. The Mk18 can be found with just about any accessory out there in use (mostly not authorized by Crane). The most common rail systems are the Knight’s Armament Company RIS and RAS. However, the NAVY EOD (Explosive Ordnance Disposal) has procured CASV-EL rail systems from VLTOR that are tan color. These weapons were equipped with A.R.M.S. #40 back-up sights. Most EOD MK18s will be equipped with M68 reflex sights on LaRue mounts, but EOTech holographic sights are showing up as well. Another interesting accessory EOD purchased was the Arrandondo magazine well adapter, which is an extended magazine well that makes speed reloading faster and easier to accomplish at night. EOD procured 1,100 tan color GripPods and A.R.M.S. #40 back-up iron sights. The GripPod (NSN 1005-01-541-1772) is a fairly new accessory introduced in 2003 that has seen major use with the Special Operations Forces as well as the military at large. The GripPod won the CQB and Midrange Bipod contract by U.S Army at Picatinny Arsenal for nearly 100,000 units. GripPod is currently shipping 200,000 GripPods to the U.S. Marine Corps to field one for every infantry marine. This vertical pistol grip doubles as a grip and a bipod. By pressing a button, a bipod springs out from the base of the grip at the speed of 1/90th of a second. The length of the unit is long enough to allow the shooter to freely maneuver with a 30-round magazine in the weapon. The unit folds by grasping both legs together and pushing them back up into the pistol grip. This enabled the troop to drop to the ground with his Mk18 and go prone, but supported.

Back-up sights are also not standard. The most common is the Lewis Machine & Tool sight. This is a fixed position rear sight identical to the standard A2 fully adjustable rear sight. If this sight is used, the optics will have to be risen to the point of aim with the sights. Also common are the Knight back-up sights – both fixed and adjustable elevation models that is part of the SOPMOD kit. Also common are the A.R.M.S. #40 and #40L back-up sights. Also used is the Matech sight. As with the M4 and M16A4 weapons, a plethora of aftermarket sights can be seen on government weapons in Iraq and Afghanistan as Uncle Sam has not had enough to go around.

Optics is not standard for the Mk18 Mod 0. Depending on what unit they are going to will determine their optics as well as availability. The most common optics would be the SOPMOD Trijicon ACOG reflex and day optical scope, and the AimPoint M68 red dot sight. Also, the EOTech holographic sight has been seen in use. The MK18 is best used with reflex sights and not magnified scopes. The purpose of the MK18 is close quarter battle and reflex sights are perfect for this task.

The Mk18 Mod O has proven itself in many different arenas of combat. The Navy uses them for boat security, boarding teams in their fleets, EOD, SEALS and Search and Rescue units. SOCOM has issued them as well. They may be seen n the hands of Rangers, Airborne troops, Green Berets as well as Operational Detachment Delta. The modularity of the M16/M4 systems is what has kept it the U.S. military’s weapon of choice for more than 40 years. Short barreled versions have served well in the caves of Afghanistan. The M4 carbine and Mk18 carbines has been the weapon of choice in Iraq for many reasons. These include increased mounted units as well as urban combat where targets are at close range. Colt Defense had designed a CQBR version of their OICW candidate with this barrel length as well. However, the OICW was a piston operated system with Colt’ proprietary monolithic upper receiver.

Another secret to the Mk18 Mod 0 carbines success is the adoption of the Mk262 Mod 1 ammunition. As a rule, the shorter commando barrels decrease the velocity of the projectile so much that a tremendous amount of energy is lost so the main advantage of the 5.56mm cartridge, hydrostatic shock, is minimized. The projectile will just go through the target or splinter and come apart. The M855 ammunition exacerbates this problem even more. As with the M4 and M16A2/A4, the inconsistency of terminal performance of the issued duty cartridge has caused problems in the Global War on Terrorism. When these thin, malnourished “evil doers” are struck with the M855 projectile, they go right through. The yaw rate is very inconsistent and varies from lot to lot. Due to the penetrator core, the accuracy potential of the weapon is not realized. The M855 is ideal for asquad automatic weapon, but not a rifle where accuracy of the single shot is more critical then laying down a heavy volume of fire on buildings, vehicles or other barriers. SOCOM saw this problem and turned to the USAMU (United States Army Marksmanship Unit). SOCOM at the time was working on the SPR, destined to be the Mk11 Mod 0 and 1 rifles. They were looking for a long range match-grade combat 5.56mm cartridge. The USAMU had already developed an incredibly accurate long range cartridge that would deal with SOCOMS issues. The 77-grain Sierra Open Tip Match projectile showed excellent sub-minute of angle accuracy. However, SOCOM needed to militarize it and turned to Jeff Hoffman at Black Hills Ammunition. They told him what they wanted, and he provided the most accurate combat 5.56mm ammunition in the world. Some of the things Hoffman did was use a stronger military brass, crimped and sealed primer, flash inhibitor and worked with Sierra to produce a 77-grain OTM with a cannulure. Not only was this ammunition incredibly accurate, but extremely and consistently lethal. Due to the long profile of the projectile, when the bullet strikes a target it quickly begins to yaw and splinter in the same manner as the M855 projectile. It would perform consistently regardless if the round came from a 20, 18, 14.5 or 10.3 inch barrel. Now SOCOM’s ammunition of choice, the Mk262 Mod 1 ammunition has proven itself in the caves of Afghanistan and Iraq. The M855 ammunition has much responsibility in the terminal performance of the M16/M4 families of weapons. The early M193 ammunition inflicted more destructive wounds than the M855. The Mk262 picks up where the M193 let off, but with the benefit of long range precision accuracy.

Research for this topic was quite difficult due to there being no standard weapon. The variations are numerous depending on where they were procured, equipment available at the time of procurement, unit purchased and individual purchased equipment used on the Mk18 Mod O. Shown in this article are the most common variations found. I would like to acknowledge the assistance of Karl Lewis, President of Lewis Machine and Tool, David Lutz of Knight’s Armament Company, William Keys of Colt Defense, Joe Moody of GripPod and Eric Kincel of Vltor for all of their technical assistance and providing the equipment to show in this detailed study.