I learned a lot of things in the Marine Corps. One thing I learned is that cheating and bending the rules are two different things. Conducting a platoon vs. platoon field op? Well, is it cheating if I go to the headquarters’ tent to ask Gunny for a water jug and snap a photo of the map showing every platoon’s location? Nope, it’s gathering intel. That’s rule-bending.
And the Marine Corps pulled their own version rule-bending when they took the M27 Infantry Automatic Rifle and used it as their official service rifle replacement.
The Army has conducted what seems like half a dozen attempts to replace the M16/M4 series of rifles, and they typically spend a ton of money and accomplish nothing. The Marine Corps adopted the M27 IAR originally to replace the SAW. IAR stands for infantry automatic rifle, and the Corps wanted to replace the SAW with an automatic weapon that was lighter and more maneuverable.
The M27 IAR replaced the SAWs, then it became the Designated Marksman Rifle, and now it’s the issued rifle to every Marine Infantrymen and most of the combat arms. Sneaky Marine Corps. What’s interesting is this is not the first time an IAR has been issued over a belt-fed weapon. In fact, this is the fourth time the U.S. Military has tried to use an automatic rifle in the squad support role.
Here are the three other times we’ve done this dance.
The Browning Automatic Rifle
The O.G. infantry automatic rifle came from John Moses Browning. It was initially designed for WW1, and at the time, Browning’s son was serving overseas. The BAR was produced a little too late for World War 1, but as we know, WW1s sequel came around, and WW2 gave the BAR some action.
Like a lot of action. It served admirably in Europe, the Pacific, and North Africa. Chambered in the powerful 30-06 round, the M1918A2 BAR spat 30 caliber man stoppers at a relatively slow and controllable 300 to 450 rounds per minute. At a time where most rifles were bolt actions and most machine guns weighed hundreds of pounds, the BAR offered some serious firepower and mobility.
It made a big difference and allowed the United States doctrine of maneuver warfare to succeed across the globe in the face of unparalleled evil. The BAR didn’t see the end of its service until the early days of Vietnam. Even then, it saw plenty of action with South Vietnamese forces. However, a 4 foot long nearly 20-pound rifle wasn’t exactly efficient by modern standards.
By the time Vietnam came around, the M14 was the rifle of choice, and the M60 had become one of the first true general-purpose machine guns. The M60 was carried by dedicated machine gunners and weighed almost 24 pounds. It didn’t fill the gap of a light machine gun, so the U.S. Army Ordnance board went about designing an infantry automatic rifle version of the M14.
Do you ever wonder why we have an M14 and an M16 but no M15? Well, the M15 was a heavily modified M14 made for the squad automatic role. Known as the M15 Squad Automatic Weapon, the rifle was identical to the M14, except it wore a heavier barrel and stock, a front and rear pistol grip, a hinged buttplate, and a bipod.
However, it was never fielded because it turns out an M14 with a bipod and hinged buttplate performs just as well as the M15. So what we saw was the M14E2, which became the M14A1. The M14A1 utilized a bipod, a BAR sling, a folding vertical pistol grip, a rear pistol grip, a plastic upper forend, and a muzzle compensator.
Some went to Vietnam, but this infantry automatic rifle kind of sucked. The BAR’s extra weight and slow firing rate made it successful. The lighter M14A1 and its 750 round per minute firing rate made it overheat quickly and hard to control. It was abandoned, and it seems most were given to ARVN ( Army of the Republic of Vietnam) forces.
The Stoner 63 Automatic Rifle
Marines took several hundred Stoner 63s to Vietnam for test and evaluation. The Stoner 63 had various configurations, including rifles, machine guns, and the infantry automatic rifle variant. The infantry automatic rifle variant utilized a top-feeding magazine, just like the European Bren guns. It chambered the lighter 5.56 round, fired full-auto only from an open bolt configuration, and utilized a bipod for additional control.
During testing, the Marines found the automatic rifle version to be useless and turned them in. It was an interesting design, but magazine-fired weapons don’t provide the best suppression in vicious firefights. The top-loading magazine allowed for a good low prone with a bipod, and the gun was superbly light compared to the M60, but no one loved it.
In the 1980s, the USMC fielded a more modern infantry automatic rifle. Kind of. In fact, at the time, it was actually an older weapon. Marine fireteams each featured an automatic rifleman armed with a full auto M16A1. The only real change they made to the rifle was attaching a bipod to it.
The M16A1 offered a full-auto setting and was actually quite controllable. With its closed bolt design, it had some of the better traits of a rifle in the automatic rifleman position. The poor Marine issued an infantry automatic rifle carried upwards of twenty magazines though.
The M16A1’s downfall as an infantry automatic rifle really came down to the fact it wasn’t designed for that role. It would overheat quickly, become too hot to handle, and again, 30 round magazines don’t provide much long-term firepower.
Is An Infantry Automatic Rifle a Bad Idea?
We’ve seen the rise and fall of the infantry automatic rifle over and over again, so that leads us to ask, is it a bad idea? Well, admittedly, an automatic rifle cannot provide the same level of firepower as a belt-fed machine gun. A magazine-fed firearm just can’t match a belt.
However, a lighter, more maneuverable weapon fits a rapidly moving force like the USMC a good deal better. Most Marine Corps platoons receive support from a machine gun team with medium machine guns. Also, when you outfit everyone with an M27 Infantry Automatic Rifle, then everyone has suppression capabilities, and the gap between an IAR and a real machine gun lessens considerably.
The USMC’s M27 features a design that is made for full-auto fire. Also, each infantry company will keep six SAWs in the armory, just in case a platoon needs a little more firepower. The adoption of an infantry automatic rifle can be done correctly, and it seems like the USMC just might be doing so.
Plus, they Trojan horsed a new service rifle into the Corps without a big expensive trial and upheld the greatest tradition of being the step-child fighting force. What say you folks? Can an IAR work in the infantry?
Or should we go back to belt feds? Let me know what you think below.