While the Army looks to upgrade the M4 with a heavier barrel, full-auto fire control group, and a piston-operating system, the Corps is taking a pass. Instead they are opting to stick with their M16A4 rifles…
For now, at least.
The M4 carbine hasn’t won many converts inside the Marines, which prides itself as being riflemen with a long history of marksmanship at ranges far beyond the 200 yard practical range of the M4.
The Marines have considered other weapons systems in 7.62 and 6.8, but have so far decided to wring the most out of existing designs.
The Corps has considered alternatives to 5.56mm ammunition to increase rifle stopping power, Commandant Gen. James Conway said Aug. 22, but officials decided instead to “make sure we’re getting all we can” from existing ammo fired from the M16. Those alternatives included 7.62mm and 6.68mm weapons, Conway said, adding that cost is one factor precluding the Corps from adopting either of them.
“We have looked at a 7.62 system,” he said. “We looked at a 6.68 system that had interchangeable barrels and receiver. But before we go to something like that and go to a completely new rifle, which would be fairly expensive for us, we want to make sure we’re getting all we can out of the cartridges we fire” out of the M16.
For now that means seeing how much performance they can wring out of the SOST round (MK318 MOD 0) developed for SOCOM’s SCAR Mk16. If the Corps has any plans beyond a proposed M16A5 stock modification they are keeping their plans to themselves.