US Special Ops Fields Caliber-Swapping MK24 Rifle For 7.62 Combat And 6.5 Range
A new rifle heading to U.S. special operations forces can switch between 7.62mm NATO and 6.5mm Creedmoor ammunition in roughly a minute, giving operators a way to adapt to changing mission requirements without carrying separate weapon systems.
MK24 modular rifle (LMT Defense on Facebook)
The weapon, known as the MK24 Medium Range Gas Gun Assault (MRGG-A), will begin reaching units before the end of the fiscal year. U.S. Special Operations Command (SOCOM) selected the platform to replace the MK17 SCAR and awarded manufacturer LMT Defense a 10-year, $92 million contract last year. The rifle also supports SOCOM's broader effort to improve performance at longer ranges while maintaining flexibility in the field.
The MK24's defining feature is its quick-change barrel system. Operators can swap between 7.62mm NATO and 6.5mm Creedmoor configurations in about a minute, allowing the weapon to adapt to different operational needs.
The requirement emerged from real-world deployment challenges. U.S. forces frequently operate alongside partner militaries that rely on different ammunition stocks. By allowing rapid caliber changes, the MK24 can continue using widely available 7.62mm rounds while giving operators access to 6.5mm Creedmoor when missions demand greater accuracy at distance.
LMT Defense designed the rifle around a 14.5-inch barrel, creating a package closer in size to an M4 carbine. Despite its compact footprint, the weapon aims to deliver the performance expected from larger precision-focused systems.
The adoption of 6.5mm Creedmoor reflects years of testing by SOCOM as it evaluated alternatives to legacy military cartridges. The command examined nearly two dozen ammunition types and reportedly found that 6.5mm Creedmoor delivered some of the strongest overall performance at ranges approaching 1,000 meters.
That advantage has attracted growing interest across the military. While 7.62mm NATO remains a mainstay of U.S. forces, newer cartridges have demonstrated improved long-range accuracy and energy retention. The Army has already started introducing its Next Generation Squad Weapons chambered in 6.8x51mm as part of a similar modernization effort.
For SOCOM, the shift is not simply about replacing ammunition. The command has spent several years searching for weapon systems that can engage targets farther away while reducing logistical burdens on deployed units.
Expanding Long-Range Capabilities
The MK24 is one piece of a wider small-arms modernization program. In recent years, SOCOM has explored new rifles and machine guns capable of extending engagement distances beyond those of existing platforms.
Those efforts resulted in contracts for a new 6.5mm sniper rifle from Geissele Automatics and a lightweight machine gun chambered in .338 Norma Magnum from Sig Sauer. Although fielding of the machine gun has been paused, the programs reflect SOCOM's interest in cartridges that offer greater effectiveness at extended ranges while reducing system weight.
Officials involved with the program have highlighted the MK24's accuracy and adaptability as major advantages. Beyond replacing the MK17 SCAR, the rifle introduces a modular approach that allows a single platform to fill multiple roles. As fielding begins, the weapon will give special operations units the ability to move between 7.62mm combat loads and 6.5mm long-range configurations with minimal disruption in the field.
The 6.5 Creedmore is a very capable round but I wonder how the barrels will hold up. I also hope they don't cripple the 6.5 with the 14.5" barrel LMT displayed at SHOT. That would place a severe limitation on an otherwise impressive cartridge.
I'll also be very interested to see what the AMU can wring out of the MK24 platform and whether it will be accepted into the U.S. Army Small Arms Championship matches at Fort Moore and the CMP matches at Camp Perry. That would change the 600/1000 yard game significantly. Surely the AMU won't be able to resist, LOL.
The switch barrel capability seems like a nice option but I think it has more to do with barrel service life and field repair than swapping calibers (a total guess on my part).
I'm fairly familiar with shooting the FN's. I have a SCAR-16 (a promo gift as part of an FN dealer package) that I have about 600-750 rounds through, and I have about 300 rounds through various customer owned SCAR-17's (training rounds--we rarely see the SCAR's in for repair).
I don't shoot the 16 any more as I don't find the SCAR's comfortable to shoulder and I've (apparently) concluded there's little advantage over the AR platform. More through neglect than conscious thought I've relegated the SCAR-16 to safe queen status. It just seems to get shuffled further and further back.
There's nothing wrong with the SCAR design. We can debate about gas systems all day, but I have piston-driven AR's that run at least as well as the FN's. The SCAR's are just...bulky? And I'm not a fan of the buttstock ergonomics.
Not a hater, just not for me.
SOCOM can have pretty much whatever they want and the fact that they've snubbed the 20S in favor of the AR platform tells me I'm not alone.
The good news longer term is that Lake City overruns of 6.5 Creedmore will drive down ammo costs (eventually--don't hold your breath any time soon) and I fully expect MK24 clones to flood the market as retail interest in anything tagged "SOCOM" drives demand.
