By Scott R. Gourley
As the fourth generation of the M16, the M16A4 rifle features performance equal to the M16A2 but offers enhanced operational flexibility through the integration of a flat-top MIL-STD-1913 accessory mounting rail integral with the weapon’s upper receiver, four additional mounting rails surrounding the barrel and a full-range backup iron sight.
In terms of program significance to the modern warfighter, a spokesperson for the U.S. Army Project Manager Soldier Weapons (PM SW) explained, “The M16 family of weapons has been and still is the main battle weapon of the U.S. Army. Every soldier in the last 40 years has trained and qualified on a version of the M16.”
Located under Program Executive Office Soldier (PEO Soldier), the project manager’s office includes both Product Manager Crew Served Weapons and Product Manager Individual Weapons.
The PM SW representative continued: “The latest incarnation of the M16, the M16A4, is an improved model with a flat-top upper receiver, backup iron sight and rail adapter system included in the standard Army configuration. The M16A2 and M16A4 weapon systems support the soldier by being compatible with all of the latest weapon-mounted optics, accessories and ammunition. The reliability of this weapon system continues to meet or exceed the Army’s requirements. The construction and operating system is well-known to the soldiers and is generally easy to care for and keep operational. Although the M4 (a carbine version of the M16) is being fielded as the main battle weapon for brigade combat teams, the M16 family of weapons (M16A2 and M16A4) is still the most used in the Army.”
Weighing 7.5 pounds without magazine (plus 1 pound for loaded 30-round magazine), the M16A4 has a barrel length of 20 inches and overall length of 39.6 inches. Firing 5.56 x 45 mm NATO standard ammunition, the M16A4 has a muzzle velocity of 3,100 feet per second and effective range (against area target) of 600 meters. Fire-control selections include safe, semi-automatic and three-round burst, with a cyclic burst rate of 700–950 rounds per minute. In addition to the ability to affix a wide range of operational subsystems to the integral mounting rails, the M16A4 can be easily enhanced through the addition of the M203A3 grenade launcher, providing the warfighter with both point and area engagement capabilities.
Emphasizing that “the M16 family of weapons is the main battle rifle of the U.S. Army,” a PM SW representative characterized current M16A4 program status: “The M16A4 Army production is complete with a density in excess of 65,000. The M16A4 is being sustained and will remain in Army inventory for the foreseeable future. The M16A4 is still in production for other services and foreign military sales.”
The most recent M16A4 production activities have been carried out by two different contractors. The government originally announced its intent “to issue a 100 percent small business set-aside solicitation resulting in a 5-year indefinite delivery, indefinite quantity (IDIQ) contract. The item to procure is the M16A4 rifle, NSN 1005-01-383-2872, PN 12973001.” With minimum guaranteed quantity of 6,857 weapons and contract maximum of 58,500 weapons, the procurement strategy soon evolved into “set-aside” and “non-set-aside” portions.
Part of the production was awarded to Colt Defense LLC in March 2007 with a second portion awarded to FN Manufacturing in December. Colt literature notes that the fourth generation of the M16 “still represents the world standard by which all other weapons of this class are judged. Its combat-proven performance is verified by the fact that over eight million M16 weapon systems have been produced and placed in military service throughout the world.”
“[The latest production] wound up being a split,” explained Joe Taylor, M16 business manager at FN Herstal. (FNH is responsible for sales, marketing and development for many of the products manufactured by FN Manufacturing, with both entities under the corporate umbrella of FN Herstal.)
“It’s interesting, because last year, in early 2007, we actually visited the PM Individual Weapons office up at Picatinny [Arsenal, N.J.],” Taylor continued. “We were trying to get some feel for what was in the future. And they actually told us that the Army was no longer buying the M16. So we figured that, for a while anyway, we would be ‘cold.’ And in actuality, we did go cold on our line from roughly the end of the year  until [spring] of 2007. Then we suddenly got solicitations from the Army. Within the period of a couple of weeks, we wound up with two contracts and then the one we are talking about right now, which is the IDIQ coming at us. So basically we went from ‘zero production’ in April of 2007 to a rate of kicking out 8,000 a month in June of this year.”
Acknowledging that the current production weapons are going to foreign military sales and the U.S. Marine Corps, Taylor added, “I don’t mean to steal any of the thunder from the Marine Corps, but I think they were pretty much convinced that they needed a little longer barrel [than the 14.5-inch barrel on the M4 carbine]. They are very concerned about shortening the weapon somehow.”
In support of that desire to shorten the M16A4, Taylor noted that FN was one of several manufacturers to come up with a new adjustable buttstock design that includes both adjustable length and hydraulic buffer. A half dozen of the new buttstock designs have been provided to the PM Infantry Weapons for the Marine Corps as well as one or two delivered to the Army Marksmanship Unit at Fort Benning, Ga. The company is currently waiting for feedback from those sites.
While the adjustable buttstock represents one possible area of enhancement, Taylor was careful to note that enhancement opportunities are somewhat limited.
“When we get a contract for the M16, basically the government has a technical data package to which they have the licensed rights or government use rights. When we get the contract, we sign a document with a nondisclosure statement, which allows us to use that technical data package only for that specific contract. In essence, we as a manufacturer are taking their drawings and their design and making it exactly to the specifications that they called out in that technical data package. We get calls many, many times, saying things like, ‘It would be great if you could make this improvement or that improvement to the M16.’ For all intents and purposes our hands are bound, unless we can convince the government or the owner of the drawing that the change would be beneficial. It’s frustrating to us when users call and say, ‘I know how we can improve this.’ And it’s very hard to explain to them that our hands are tied in that regard.”
Prognosticating on a far-term Army small-arms future that might capitalize on design features found in programs like FN’s current special operations combat assault rifle, Taylor concluded, “As for the future of the M16A4, I’m sure we are going to be building those for quite a while. Everybody has been saying since the 1970s that the M16 is a legacy weapon. But it’s currently the best thing out there.”