A survey of more than 50 servicemen who have fought in Iraq and Afghanistan concluded that the 5.56mm calibre rounds used by British soldiers 'tailed off' after 300 metres yet half of all Helmand firefights are fought between 300 and 900 metres.

Mattis pushed for 6.8mm ammo
By Dan Lamothe - Staff writer
Posted : Friday Mar 12, 2010 15:01:07 EST

Before Marines in Afghanistan received enhanced 5.56mm rounds last month, an influential four-star general advocated behind the scenes for an option that packs even more punch: 6.8mm ammunition.

Three sources with knowledge of the Marine Corps’ acquisitions process confirmed Gen. James Mattis’ interest in the 6.8mm round, saying the head of Joint Forces Command in Norfolk, Va., lobbied for it as recently as December while pushing broadly for better service-rifle ammo.

“It’s something he was definitely interested in,” said one source, speaking on the condition of anonymity due to the sensitivity of the subject. “He was concerned with the stopping power of the M855,” the standard 5.56mm round that the U.S. military has used for decades.

Instead, the Corps adopted enhanced 5.56mm Special Operations Science and Technology ammunition, commonly known as SOST rounds. Using an open-tip match round design common with sniper ammo, they are designed to be more accurate and more deadly than M855 rounds, staying on target better after penetrating windshields, car doors and other objects.

Mattis declined to comment, saying he is confident Lt. Gen. George Flynn, commander of Marine Corps Combat Development Command, is “dealing well with this complex issue.” Flynn could not be reached for comment.

Behind the scenes, Marine officials have discussed for years whether a larger-caliber round is necessary. Some have said the Corps should adopt an intermediate caliber, such as 6.8mm, or go back to 7.62mm, which was widely used until the M16 was fielded in the 1960s.

The Corps is still considering a swap to larger calibers, but if SOST continues to show promise, it may not be necessary, said Chief Warrant Officer-5 Jeffrey Eby, the Corps’ senior gunner. Marine officials “100 percent trust” the new round, he said, and are awaiting feedback from operating forces who are beginning to use it.

THE CALIBER QUESTION
The Corps first considered fielding 6.8mm ammo in 2007, after rank-and-file members of Special Operations Command designed it with their command’s approval to address deficiencies with the standard 5.56mm round, Eby said. Neither SOCom nor the Corps fielded it, in part due to the cost and logistics it would have required to make the change.
Designed to be fired from existing M4 and M16A4 service rifles after some modification, the 6.8mm special-purpose cartridge travels at higher speeds and inflicts more damage than the M855, but is lighter than standard 7.62mm ammo. The 6.8mm round is only slightly longer than 5.56mm ammo, meaning it would fit existing service-rifle magazines and lower receivers.

Adopting the intermediate caliber wouldn’t be easy, though. The ballistics are different than the 5.56mm rounds’, which would require the service to adjust training and adopt new optics for their service rifles, Eby said. It also would require ammunition manufacturers to reconfigure machinery, potentially costing the service tens of millions of dollars or more.

Fielding 6.8mm ammo also would result in new marksmanship challenges. Much like the 7.62mm M14, a 6.8mm rifle produces larger recoil than an M16A4 or M4, making it difficult for smaller Marines to keep the weapon on target, Eby said.

“We learned with the M14 that managing that recoil across the service, especially with small-stature women and men, is hard to do,” Eby said. “If we have problems today with bucking and flinching on the 5.56, you can quadruple that with 7.62. We have service-level concerns about [going] so big that you get the ultimate lethality at the expense of marksmanship.”

Brig. Gen. Michael Brogan, commander of Marine Corps Systems Command, told Marine Corps Times in mid-February that “there’s a long-going argument about the stopping power of 5.56 in general.” But he said even Marines don’t always fall after they’ve been shot by insurgents with multiple 7.62mm rounds, citing Navy Cross recipient Sgt. Maj. Brad Kasal, who was hit with seven 7.62mm rounds in Iraq in 2004 but survived and kept fighting.

“Does that mean that 7.62 rounds don’t have sufficient stopping power?” Brogan asked about Kasal’s actions. “I submit the answer is no. If there had been a central-nervous shot, it might have dropped him. The same is true with 5.56 ammunition. Location is more important than stopping power.”

FN Herstal, S.A. (FN) received notification from the USSOCOM Program Executive Office—SOF Warrior (PEO—SW) that the SCAR Acquisition Decision Memorandum (ADM) was approved and signed on April 14, 2010, moving this FN program into the Milestone C phase.

This decision authorizes the production and deployment of the Special Operations Forces (SOF) Combat Assault Rifle (SCAR) MK 16 and MK 17, as well as the Enhanced Grenade Launcher Module (EGLM) MK 13.

Following a worldwide solicitation to the military firearms industry, nine vendors submitted a dozen different designs for a new modular, multi-caliber weapons system. The FN SCAR submission was the only weapons system to pass all of the Go/No-Go criteria and was unanimously chosen in November 2004 by the selection board composed of senior operators from every SOF component.

The SCAR is the first new assault rifle procured by the U.S. military through a full and open competition since the M16 trials were held in the mid-1960s. Tests in reliability, accuracy, safety and ergonomics were administered from August 2005 to September 2008 and were conducted in a variety of environments including urban, maritime, jungle and winter/mountain operational test scenarios.

The SCAR weapons system successfully endured more than two million rounds of ammunition during these trials, therein making it one of the most heavily tested weapons in the history of small arms.

The FN SCAR system consists of two highly adaptable modular rifle platforms and a grenade launcher. Type-designated as the MK 16 MOD 0 5.56mm Special Operations Forces Combat Assault Rifle and the MK 17 MOD 0 7.62mm Special Operations Forces Combat Assault Rifle, both weapons are available with three different barrel lengths optimized for conducting operations in close-quarters combat, standard infantry and longer-range precision fire roles.

All SCAR barrels can be easily interchanged by the operator in just minutes to instantly meet the requirements of virtually any mission. The MK 13 MOD 0 40mm Enhanced Grenade Launcher Module (EGLM) quickly mounts under the barrel of either SCAR platform, providing additional capability to the individual warfighter’s firepower, and can be easily configured for use as a stand-alone weapon as well.

Because of the SCAR system’s modular design, ergonomic commonality (100%) and parts commonality (greater than 80%), it represents a significant reduction in training costs and life-cycle support. The weapon system’s open architecture is designed to support future advancements in operational requirements including ammunition, aiming devices, sighting systems and other mission critical equipment.

And if a weapon’s caliber is not 5.56mm or 7.62mm, the manufacturer must provide 234,000 rounds to cover all tests.