The Marine Corps is exploring a service rifle overhaul that could lead to the adoption of adjustable butt stocks, free-floating barrels and common slings on more than 200,000 weapons.
The proposals, among those recommended recently at the 2011 Combat Marksmanship Symposium, could lead to some of the most significant upgrades to the Corps’ service rifles since the 5.56mm M16A4 and M4 were adopted early during the Iraq war.
Some of the updates have been under consideration for years, but were sidelined by the Corps’ approval process and philosophical differences among top Marine officers. It isn’t assured that all of the upgrades will be adopted, but they have unified support from Marines who oversee marksmanship, said Col. Timothy Armstrong, head of Weapons Training Battalion, based at Quantico.
The recommendations will be pushed up the chain of command, and Marine Corps Systems Command will lead acquisitions projects.
“We are exploring potential materiel solutions where tactics, techniques and procedures will not resolve the issue,” said Barbara Hamby, a MARCORSYSCOM spokeswoman.
The Corps currently has more than 200,000 M16A4s and 80,000 M4s in its inventory, with the M16A4 serving as the primary rifle. The service issues M4 carbines primarily to vehicle operators and other Marines whose jobs render the M16A4’s 20-inch barrel cumbersome. The M4 has a 14.5-inch barrel, making it better in close-quarters combat, but diminishing accuracy and stopping power, especially at ranges beyond 200 yards.
The symposium was held in March, and recommendations were released June 3 in Marine administrative message 320/11. Weapons Training Battalion officials elaborated on the plans in aninterview with Marine Corps Times. They include:
The M4 already has an adjustable butt stock on it, a development that enables soldiers and Marines to shoulder their weapon better, even while wearing body armor. The M16A4 does not, however, creating problems for shorter Marines, who struggle to get enough distance between their shooting eye and the optic while aiming.
At the symposium, marksmanship officials backed replacing the M16A4’s solid, 11-inch stock with an adjustable one similar to the M4’s, adding momentum to an argument that dates back years.
Historically, critics have questioned whether eliminating the solid M16A4 stock would weaken a workhorse weapon. It’s effective in hand-to-hand combat, where a butt stroke can be used to kill or incapacitate enemies, they say. The stock also comes in handy during the two-man lift, where two Marines hold each end of a weapon and hoist a third grunt over a wall or into a second-story window.
Proponents of the adjustable stock say those arguments are outdated and holding up progress. The Army has used the M4 as its primary service weapon for years with few complaints about its stock, they point out. Adjustable stock advocates also say the two-man lift and butt-stroking are uncommon, and in a pinch, the barrel of the rifle can be swung to incapacitate or kill a combatant.
Each of the changes they have proposed, including the butt stock swap, is rooted in analysis to improve combat effectiveness, Armstrong said.
“We’re trying to institute change in an organized fashion, based not off emotion or who talks the loudest,” he said. “It’s more looking at the data and the true analysis that takes place.”
Marine officials also recommended adopting a free-floating rail system on all M16A4s and M4s. It’s a technique already used to increase accuracy on many of the Corps’ weapons, including the 7.62mm M40 and M110 sniper rifles and the 5.56mm M27 infantry automatic rifle.
Barrels of both the M16A4 and M4 attach to the rest of the rifle in several locations. That can affect accuracy, both in combat and on the range. For one, if tension is placed on a weapon’s sling incorrectly to draw a rifle close to fire, it can pull the barrel out of alignment with the optic, throwing off the zeroing of the weapon.
Incorporating a free-floating rail system would connect the barrel only with the receiver. That would keep the weapon’s zeroing truer, even when the rifle was placed under heavy sling tension or the weight of optics, pointers and other equipment.
“I’m not saying we’re not getting excellent results right now, but we are teaching them to compensate for the fact that it’s not a free-floating barrel,” said Chief Warrant Officer-3 Christian Wade, a gunner at Weapons Training Battalion. “It would be easier if it was, without a doubt.”
Marksmanship officials recommended that the adjustable butt stock and free-floating rail system be added on existing rifles at the same time.
Marksmanship officials also backed the Corps adopting a common weapon sling that can be used anywhere, including during qualifications on all four tables of the Known Distance course of fire and in combat. The sling that will most likely be pursued for common use will have two points and work on all M4s and M16A4s.
Marines today use a variety of slings, and units frequently purchase their own with supplemental money received 180 days before deployment.
“Through testing and evaluation, we’re trying to get the Marine Corps steered toward a sling that has the most, broadest utility for the money,” Wade said.
One exception: The Corps will continue to field separate “parade slings” for use during ceremonies.
Eye-relief enhancement kit
An eye-relief enhancement kit for the M16A4 should be adopted Corps-wide as an interim solution until the adjustable butt stock is adopted, marksmanship officials also recommended.
The kits would allow Marines to keep their shooting eyes far enough from their optics to avoid getting hit in the face after a weapon recoils. Ideally, a Marine should have about 1½ inches of “eye relief” while looking through an optic. Currently, that’s a problem for many Marines, especially when body armor changes how the solid stock is shouldered.
The kit mounts to the rifle’s Picatinny rail, adding adjustable brackets that help a Marine mount his optic in the correct spot, given his height, arm length and the equipment and uniform he is wearing. It already has been fielded to thousands of Marines in deploying infantry battalions and has been tested by lieutenants in marksmanship training at The Basic School at Quantico.
Statistics were not available, but adding the kit to a rifle has helped to boost entry-level training scores there substantially, Wade said.
Marine officials also backed the adoption of a different optic mount for nearly every rifle. Currently, the TA51 mount made by Trijicon is used to attach an optic to the rail of an M16A4 or M4. Marines tighten thumb screws to fasten it in place, and are ordered to use a small screwdriver or piece of metal to make sure it’s tight. They’ve been known to shake loose, however, especially when a Marine is involved in a firefight or some other situation where he is sending a lot of lead downrange in a short period of time.
Marksmanship officials backed a shift to a different mount made by Larue Tactical. Instead of thumb screws, it uses small “throw levers,” making it easier to remove a scope if a Marine needs to transition to his backup iron sights. The optic also doesn’t come loose the way it can when thumb screws work their way free as a weapon vibrates.
The Larue mounts will already be familiar to some Marines. They have been used for several years to mount optics to the M249 squad automatic weapon, Wade said. The Larue mounts also have been issued with the Corps’ IARs, which use the SAW day optic.
The symposium also yielded one recommendation that won’t require many changes: Make sure ambidextrous controls are issued to units for left-handed shooters. Currently, many units buy the controls, which make the magazine release and selector lever quickly accessible to southpaws, whose trigger-hand thumbs are on the opposite side of the rifle.
Marksmanship officials recommended that the Corps issue ambidextrous controls to unit armories to be installed as needed for left-handed shooters. They shouldn’t be adopted on all rifles, however, Wade said. Doing so would cost unnecessary money and add unneeded moving parts to right-handers’ rifles, he said.
story by: Dan Lamothe
photo courtesy of: USMC