U.S. Marine Corps infantrymen could soon switch to the M4 from the M16. Pictured: Marine Corps Cpl. Jordan Westra takes aim using an M4 rifle before firing a warning shot at Camp Barcha in Helmand province, Afghanistan, Oct. 12, 2009. Reuters

U.S. Marine Corps leaders have recommended swapping the M16 rifle in favor of the M4 carbine as the universal weapon for infantrymen, Marine Corps Times reported Monday. The proposal would mark a shift away from a weapon has been the primary gun for Marine infantry since the Vietnam War.

The switch appears "imminent," and would be a similar shift to one already being undertaken by the Army. The M16 would become a support weapon should the move take place. Final approval is possible in the coming weeks or months.

The proposed switch reportedly has been endorsed by a number of major commands, including the Marine Corps Combat Development Command; Combat Development and Integration; Plans, Policies and Operations; Marine Corps Systems Command; and Installations and Logistics.

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"The proposal to replace the M16A4 with the M4 within infantry battalions is currently under consideration at Headquarters Marine Corps," says a jointly written statement from the commands that was provided by Maj. Anton Semelroth, a Marine Corps spokesman, via the Marine Corps Times.

Infantrymen support the switch because they say the M4 is better suited to modern combat over the M16A4. The M16 was designed in 1956 and first used in service by the Army during jungle warfare in Vietnam. It became standard issue for the U.S. military in 1969.

But the longer M16 proved to be more difficult to handle in close-quarters battles in Iraq and vehicle operations in Afghanistan. Infantrymen say the M4 is lighter, easier to maneuver and has a collapsible butt stock that allows the weapon to be tailored to individual Marines. The M4 is about 10 inches shorter than the M16 and weighs about one pound less.

"I would have to say my gut reaction is it's the right choice and will do a lot of good for the guys in the infantry," said Sgt. Nathan West, an explosive ordnance technician with 8th Engineer Support Battalion, according to Marine Corps Times. He used an M4 while serving in Afghanistan. "The M4 is a great weapons system that has done everything I have ever asked of it," West added.

If Marine Corps Gen. Joseph Dunford -- the current commandant of the Marine Corps and President Barack Obama's nominee to be chairman of the Joint Chiefs of Staff -- approves the swap, the switch could happen as quickly as the new M4s can be issued. The Marines currently have 17,000 M4s in their inventory. Officials have called the swap an "improved capability for the infantry at no additional cost," Marine Corps Times reported.

The drawbacks of the switch to the M4 are not significant, infantrymen said. The M4 has a slightly shorter range -- although gun manufacturer Colt reports both have an effective range of about 650 yards -- but most modern warfare occurs in tight ranges.

Firearms expert and former member of Army Special Forces Larry Vickers fully endorsed the move. "I'm the first one to subscribe to this," Vickers said about the increased popularity of the M4 for modern combat.