Congress Set To Put the Brakes On Marine Plans To Buy More Of Its Popular M27 Rifles

A new defense spending bill would slow purchases until the service explains how the guns align with an Army-led ammunition study.

byJoseph Trevithick|
Assault Rifles photo


Congress is moving to slow the U.S. Marine Corps’ purchases of M27 Infantry Automatic Rifles, or IARs, in a new defense spending bill for the 2019 fiscal year. Lawmakers want to withhold 20 percent of the funding for the new guns until the service better explains its own future small arms plans and how they fit with a U.S. Army-led study that calls for standard infantry weapons in new calibers to respond to emerging threats, especially improved body armor.

The provisions are included in a final draft version of the proposed defense budget law, also known as the John S. McCain National Defense Authorization Act for Fiscal Year 2019, which the House of Representatives passed on July 26, 2018. It now heads to the Senate, where it already has support, and could be headed to President Donald Trump’s desk to become law early in August 2018.

The relevant sections demand a report on the “near-term and long-term modernization strategies for small arms weapon systems of the Marine Corps” before the Marines can spend all of the money they requested to buy additional M27s, according to Marine Corps Times. That same review must include information on how the rifles fit in with the Small Arms Ammunition Configuration Study, or SAAC, which the Army, in cooperation with all the other branches of the U.S. military, wrapped up in 2017.

The ammunition question looms particularly large over the Marine’s M27 purchase program. The rifles use the same 5.56x45mm cartridge that is standard across the U.S. military. The Corps first began issuing the weapon in 2011 as a substitute for the M249 Squad Automatic Weapon, but in 2016 began moving toward issuing it as a new standard infantry weapon across the board.

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Though there is no publicly available version of the SAAC report, by all accounts it includes recommendations to adopt a so-called “intermediate cartridge” as the standard round for U.S. military infantry rifles. This category of ammunition typically refers to cartridges that fall somewhere between the existing 5.56x45mm type and the larger 7.62x51mm round, generally firing bullets between six and seven millimeters in diameter.

The Army has publicly stated that one of the driving concerns is improvements in body armor among potential opponents, including Russia and China, which could render the 5.56x45mm round ineffective, especially at the tail end of its existing maximum effective range. The service even briefly considered issuing 7.62x51mm rifles to select units as an interim solution.

Now, the Army says it has plans to adopt a new squad automatic weapon that could be in an intermediate caliber by 2022. The service has also indicated that this weapon might serve as the basis for a new standard infantry rifle or guns to serve in other specialized roles.

A pair of experimental squad automatic rifles from AAI Corporation, which may be the basis of the company's entry into the Army's Next Generation Squad Automatic Rifle (NGSAR) program., Joseph Trevithick

At the same time, U.S. Special Operations Command has announced that it is developing designated marksman rifles in a 6.5mm caliber and is looking to adopt a light machine gun firing the same rounds. However, special operations forces don't have any plans at present to substitute any of these weapons for existing 5.56x45mm rifles or carbines. It’s worth noting that the U.S. military as a whole has had an on-again-off-again relationship with six-millimeter cartridges for nearly 50 years already, but the trend does seem to be finally heading in that direction.

The primary concern legislators then have with the Marine’s plans to adopt the M27 as a new standard infantry rifle is that those guns could easily be obsolete within a matter of years. This, in turn, could force the service to either replace or substantially modify those guns if the U.S. military broadly decides to adopt a new type of ammunition as standard, either of which could be potentially costly options. 

German firm Heckler and Koch

did experiment with a version of its HK 416 rifle, which the M27 is based on, chambered in the 6.8mm Remington Special Purpose Cartridge, but it is unclear how many parts that type shared with the 5.56mm rifles. Based on examples of conversions of other AR-15/M16 pattern rifles and derivatives, this could as simple as swapping out the upper half of the gun. It’s not clear if it would be as easy to modify the weapons to accommodate any other type of six-millimeter round, though.

A slide from a Heckler and Koch company briefing in 2007 depicting a 6.8mm HK 416 carbine in between a standard 5.56x45mm model and the larger 7.62x51mm HK 417 rifle., Heckler and Koch

Still, Congress has already admonished the Marines over the steep price of the M27s to begin with. In April 2017, the service told legislators it had been able to get Heckler and Koch to drop the unit cost of the rifles down from a whopping $3,000 to around $1,300. However, this is still double the price of a new M4A1 carbine, the existing standard service weapon.

This hasn’t been the only hiccup for the IAR program, either. There have already been questions about how well the weapons work with their existing 5.56mm ammunition.

In December 2017, the Marines formally adopted the Army-designed 5.56x45mm M855A1 Enhanced Performance Round (EPR), which has been controversial in its own right, as its standard ammunition type. Testing showed the cartridges caused “some durability issues” in the M27, but the service insisted the guns were still “operationally suitable,” according to Marine Corps Times. Previously, the Corps had been primarily using the Mk 318 cartridge, which the U.S. Navy had developed at the request of various U.S. special operations forces.

A complete M855A1 EPR cartridge, at top, and the bullet itself, below., US Army

In April 2018, a leaked testing report also suggested the M27 could have reduced accuracy when fitted with the Knight's Armament Company (KAC) QDSS-NT4 sound suppressor. This accessory is in widespread use across the U.S. military and the Corps is looking to make it a standard piece of kit for infantry Marines.

The Marines, however, stand behind the gun itself and have already been pushing ahead with plans to buy and issue more M27s. In April 2018, the Corps handed Heckler and Koch a sole-source contract worth nearly $30 million for as many as 15,000 rifles and spare parts.

Marines train with M27s., USMC

“What I expect is that with the issuance of the M27 to all Marines in every squad, the ongoing mass employment of suppressors, and the development of variable power optics, every Marine in the squad will have the M38 capability in his own rifle,” retired Chief Warrant Officer 5 Christian Wade, who had previously been a member of the 2nd Marine Division and had led a number of experiments related to modernizing the service’s infantry formations, told Marine Corps Times in April 2018. “The rifleman with an M27 IAR [Infantry Automatic Rifle], suppressor, variable power optic, advanced NODs [night vision], etc. who is fully trained, is a game changer.”

But, if the latest iteration of the defense spending bill for the 2019 fiscal year becomes law, the Marines will have to, once again, make that case to Congress or risk losing funds to purchase more of the rifles.

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