Training the Automatic Rifleman Ensuring capabilities are being maximized

Training the Automatic Rifleman Ensuring capabilities are being maximized


Description:  An IAR provides a needed capability to infantry and LAR units.

Author:  Capt Travis C. Onischuk

Author:  Capt Jeff Cummings

The M27 infantry automatic rifle (IAR) is close to being fully fielded to all infantry battalions. With 2 years of combat-tested experience, we must look at our training of the automatic rifleman to ensure his capabilities with the M27 are maximized on the battlefield. This new weapons system offers unique capabilities when compared to its predecessor, the M249 light machinegun. Given that the M27 is new and far different from the M249, there are certain training challenges that must be overcome so that we as an infantry community can maximize its true potential. Over the past year, we have trained more than 300 student lieutenants at Infantry Officer Course (IOC) on M27 employment and the skills required of the automatic rifleman. During this time, multiple training challenges have been identified and training techniques developed. This article is a discussion of these challenges and techniques, and includes training recommendations to ensure that the M27 fulfills its potential as the premier infantry squad weapon.


Distinguishing the M27 From the M249

The first challenge is for our automatic riflemen to understand the M27 as a different capability than the M249. The reasoning is simple: The two weapons have different benefits and disadvantages that must be trained to accordingly. Although the M27 replaced the M249 and does provide multiple similar capabilities for each fire team, its overall employment is anything but the same. The M249 is, by definition, a light machinegun, and therefore an excellent weapon when a high volume of sustained fire is required. Conversely, the M27 is better-suited for providing accurate fires, achieving fire superiority, and, most importantly, closing in the assault. As a unit ages and new Marines join the ranks, the problem of distinguishing the two capabilities may sort itself out as M249 experience atrophies. However, this potential reality also represents a problem: The capabilities and advantages of the M249 are something we cannot lose at the platoon level. We need leadership that recognizes this fact so that platoons are trained and ready to use the M249 when missions require the advantage of a light machinegun. Ultimately, though, training must reflect the differences between the weapons. Specific to the M27, it is critical that we do not train our automatic riflemen to have the same mentality and capability as they did when they carried light machineguns.


Base of Fire

The automatic rifle is nothing new to the Marine Corps. In fact, the M249 light machinegun replaced several generations of automatic rifles, including the original M16 and the Browning automatic rifle (BAR); therefore, an extensive amount of history and experience exists for us to draw upon and help guide us in ensuring the M27 reaches its potential in combat. First, having a selector to transition between semiautomatic and full automatic gives the M27 a performance edge in many instances.

Most importantly, though, the selector creates a decision point for the user that never existed with the M249. This decision point must be trained to. Within a base of fire, the M27 should deliver a high volume of initial fire to help the fire team and squad establish fire superiority. This simple drill, called an RTR (return fire, take cover, return accurate fire) drill, should be drilled with the M27 and the M4. Once fire superiority is established, the M27 should be used primarily on semiautomatic to deliver highly accurate suppressive fire while helping to conserve ammunition for a more prolonged base of fire or for closing in a final assault. In training to this decision point, we must challenge our automatic riflemen with different battlefield stimuli and exposures. The decision point for the Marine on whether to transition from semiautomatic to full automatic should be tied to two things: first, the enemy exposure being presented to him, and second, his fires in relation to and support of a maneuver element closing on the enemy. Like the M4, the M27 can achieve suppressive effects with a single shot at a sustained rate of fire; however, if a squad is unsupported against stiff enemy resistance, semiautomatic fire alone will unlikely achieve the desired effects. A Marine’s training should reflect this reality. When training automatic riflemen skills as a base of fire, giving the automatic rifleman target exposures that simulate different enemy compositions will force him to decide which mode to fire at. Although automatic riflemen need not necessarily fire on full automatic for larger concentrations of the enemy, the drill itself is enough to get them thinking about battlefield conditions when deciding how to control their rates of fire and selection between semiautomatic and full automatic fire.

The second drill should be tied to friendly elements on the battlefield. Because a static base of fire is most often employed to allow another element to close with the enemy, our automatic riflemen must be drilled to know how to adjust their fires to best support the maneuver elements closing. The tactical control measure (TCM) most relevant in the user’s decision cycle is the final coordination line (FCL). At this TCM, the base of fire will shift fire and the maneuver element will commence its assault. The FCL is relevant because it is the closest point the supported element will get to before covering fires are lifted.1 This makes the FCL one of the most vulnerable spots for the closing element. To give the maneuvering element the best chance of kicking off its assault and keeping the enemy fixed, automatic riflemen should be drilled to transition to full automatic as the unit they are supporting closes on the FCL. This can be trained as an individual skill through the use of “paints” to the Marine being trained—that is, before he executes the drill, he should know: 1) where the FCL is, 2) where the friendly element will be maneuvering from, and 3) a basic enemy situation. Once those are established, the evaluator can provide real-time paints or updates to the maneuver element’s location relative to the FCL.2 The automatic riflemen will then need to decide when to shift to full automatic to best support the closing element before having to shift fire. When trained at the fire team level, this drill does an excellent job of testing the team leader’s ability to communicate these actions to his Marines as well as controlling their fires to best support a maneuvering element.

Automatic rifle fire and its effect comprise the second step in technique of fire training.3 Because these drills test and evaluate a Marine’s military judgment rather than technical and procedural basic skills, they should be done only after the Marine has demonstrated a high level of proficiency in combat marksmanship. Marine Corps Order (MCO) 3574.2K provides adequate guidance in marksmanship training for the rifleman.4 As the majority of fire for most engagements will likely be fired semiautomatic, automatic riflemen must be drilled with their M27s to meet the same standards as riflemen as laid out in MCO 3574.2K. Moreover, mastery of marksmanship skills takes advantage of another key feature the M27 brings to our rifle squads. A well-trained automatic rifleman can reach out and engage longer-range targets than an equally capable Marine with an M4. With greater barrel length and a free-floating barrel, the M27’s ballistics hold a tighter shot group than the M4, thus making our squads more lethal in terrain where observation, range, and ruggedness may significantly slow maneuver.5 This employment consideration is a significant shift in training philosophy from the M249. This shift should drive commanders and leaders to be more mindful of which Marines they assign as automatic riflemen; that is, to capitalize on the potential of the M27, our automatic riflemen should be the best marksmen in their squads, capable of applying sound, independent military judgment. Although principally there are similarities in employment between the M27 and M249 at places like a base of fire, other factors such as rate of fire, ammunition consumption, and accuracy make the differences too stark to try and drill the users the same way.

Assault Fire

Potentially the most valuable contribution of the M27 is its use as the weapon of choice in the assault. As a closed-bolt, fully automatic rifle designed to be shoulder-fired accurately from the prone, kneeling, and standing positions, the M27 is an extremely powerful weapon in the assault and other close-quarters situations. Although assault fire techniques are not new in concept, their practice, in some cases, has atrophied. The M27’s characteristics and capabilities provide the foundation for the Marine infantry to reenergize a focus on the application of assault fire techniques and what it takes to close the last 100 meters on a determined enemy position. We can learn a lot about the value of the automatic rifle in the assault through a close study of the M27’s predecessors, specifically the development of weapons such as the BAR and Thompson submachinegun that proved decisive in the assault and close-quarters environments. The M249 light machinegun’s characteristics make it poorly suited for this task. The M27 is absolutely the weapon of choice for these assignments.

Assault fire is defined as:

[. . .] designed to keep the enemy fire suppressed, once covering fires are lifted, by fixing the defenders in their fighting positions. [. . .] The assault is made as rapidly as possible consistent with the ability of individuals to deliver a high volume of well-directed fire. [. . .] Throughout the assault, fire is directed at every bush or tree stump, every fold in the ground, and every location that might conceivably contain an enemy.6

The Marine rifle squad publication continues its explanation of assault fire by describing techniques for each billet within the fire team. Automatic riflemen must be well trained in the pointing technique while moving rapidly to close with the objective. Emphasis of this assaulting technique must be on the accuracy, volume, and violence of fire poured on the objective. The assault is the most necessary time for our automatic riflemen to be on full automatic, thus it is during the assault that the majority of ammunition is likely to be expended by a maneuvering force. The assault must be characterized by “violence, volume, and accuracy.” Our assault fire drills must emphasize and train Marines to move quickly while engaging targets accurately from the standing position at a high rate of fire. When applied well, this technique can have a devastating effect on enemy positions when Marines are closing the last 40 meters. This technique translates well to the tough tasks of clearing rooms, trenches, and hallways, and when internally supporting the securing of a foothold on a fortified position.

Proficiency of this skill requires an aggressive training approach. Currently MCO 3574.2K does not adequately address assault fire techniques, but the beginning steps to this skill are present. For instance, in the Table III course of fire, there is limited shooting while moving; unfortunately, this is largely where the formal shooting and moving stops. What we can learn from Table III, however, is that Marines are deadly accurate with their rifles inside 50 meters, even while moving. In order to maximize the capabilities of the M27 as a devastating weapon in the assault, we must train our Marines to be ruthlessly violent, fast, and skillful in the employment of their rifle inside 50 meters. An excellent example of this technique can be trained during drills such as the exploitation of M67 fragmentation grenades, flash bangs, or other concussion grenades. Automatic riflemen and riflemen must be trained to violently exploit these assets—by fire—following their effective use. After fighting to an assault position near the enemy objective (likely inside 50 meters from the position), Marines should be drilled in their final assault techniques. First, the use of M67s or other high explosives should be employed. Second, immediately following the effective use of this high explosive, Marines from the assaulting unit, specifically the automatic riflemen, must violently exploit by fire. During such exploitation, automatic riflemen should be on full automatic and conditioned to fire at any conceivable enemy position as they seek to secure the foothold or overrun the position. Hesitation on the part of Marines during exploitation should be ruthlessly remediated.

Assault fire techniques, when applied to such ranges as Range 410A or Range 210 at Marine Corps Air-Ground Combat Center Twentynine Palms, makes the closure to gain a foothold in a trench or gain entry into a building much more violent and devastating. Further, a properly trained automatic rifleman in close quarters has a psychological effect on the enemy that the M249 cannot replicate. Unlike the M249, the M27 is the weapon of choice to lead the entry into buildings, rooms, and trenches. The ability to deliver highly accurate, fully automatic fire in these close-quarters environments is one of the greatest benefits of the M27. The automatic rifleman must now be the designated Marine to lead his fire team into these close-quarters environments.


As our doctrine states:

The science of tactics lies in the technical application of combat power. It includes mastering the techniques and procedures that contribute to the development of warfighting skills such as marksmanship, navigation, gunnery, and close air support. The execution of these techniques and procedures must become second nature for us; this requires intensive and continuous training. Without mastery of basic warfighting skills, artistry and creativity in their application are impossible.7

Both applications of training for the M27 described in this article have numerous variations based on relevant considerations facing the shooter. Does the terrain support a covered approach? Is the enemy fire so great that I must low-crawl to a grenade-throwing position rather than assault fire? Can I achieve effective suppression on an area target with a single shot and therefore have no need to transition to full automatic? Facing our Marines are these questions and many like them. Training must address these realities of war and others like them. However, we cannot use the multitude of possibilities from deterring us from training and drilling specific and rigid battle drills. The drills described above and other specific individual and team battle drills are the training foundation from which we must build. It becomes easier to challenge our Marines with different conditions only after they know the basic individual tactics, techniques, and procedures. Whether supporting a maneuver element or in the assault, the M27 has unique capabilities in providing accurate, violent fires on the enemy. Through aggressive training of our automatic riflemen (and squads), we can ensure that the Marine infantry remains the most lethal close combat force in the world.


  1. Headquarters Marine Corps, Marine Corps Warfighting Publication 3–11.2 (MCWP 3–11.2), Marine Rifle Squad, Washington, DC, 1997, p. 4–26.
  2. “Paints” are critical to enhance training and build battlefield awareness for our Marines. Much like at Tactics and Training Evaluation Control Group (TTECG), paints should be used to stimulate certain action, either to reward good decisions by Marines or punish poor actions. As such, the use of paints in providing updates to the friendly situation is an effective way to evaluate and train Marines. Paints help us evaluate their ability to control fires in support of a moving or closing element.
  3. MCWP 3–11.2, p. 2–6.
  4. Headquarters Marine Corps, Marine Corps Order 3574.2K, Marine Corps Combat Marksmanship Programs, Washington, DC, August 2007, appendix E–2.
  5. The M27 technical manual states that the maximum effective range of the weapon is 550 meters, the same as the M4. The biggest factor in accuracy, however, is the proficiency of the shooter and how well he applies the fundamentals of marksmanship. Nonetheless, the M27 holds a tighter group due to its ballistic nature.; therefore, the same shooter in the same conditions will be more accurate with the M27 than the M4.
  6. MCWP 3–11.2, p. 4–27.
  7. Headquarters Marine Corps, Marine Corps Doctrinal Publication 1–3, Tactics, Washington, DC, 1997, p. 4.

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