The U.S. Special Operations Command (USSOCOM) will introduce the Mid-Range Gas Gun-Assault (MRGG-A) before the end of the current fiscal year under the official designation Mk24. Only last August did the command task the firearms manufacturer Lewis Machine & Tool (LMT) with the delivery of the weapon from its Modular Ambidextrous Rifle System-Heavy (MARS-H) family. According to SOCOM, the Mk24 is to completely replace the FN SCAR-H, which had been introduced as Mk17.
The contract with LMT includes, in addition to an unspecified number of weapons, spare parts, accessories, training on the new equipment and proposals for design-change, with a total value of up to $92 million (about €79 million) and runs through 2035. According to the manufacturer, SOCOM requirements included a quick-change barrel to enable the weapon to be chambered for both the 6.5×48 mm Creedmoor and the NATO standard 7.62×51 mm cartridge.
MRGG-A complements MRGG-S
The publicly known configuration of the MRGG-A features a 14.5-inch (368 mm) barrel, an integrated Picatinny accessory rail across the entire top of the receiver, and M-LOK attachment points on the handguard. The weapon is fully ambidextrous and capable of both semi-automatic and fully automatic fire. For SOCOM, it may be equipped with an optic from Nightforce Optics, since LMT has already demonstrated this combination and Nightforce received in 2021 a command contract for its ATACR 4-20×50 F1 scope.
The MRGG-A is intended to complement the MRGG-S (for Sniper) with a 20-inch barrel (508 mm), a directly gas-operated sniper-support weapon of the AR-10 type, which SOCOM procured from Geissele Automatics in 2023. This also features a quick-change barrel for calibers 6.5×48 and 7.62×51 mm. The 6.5 mm Creedmoor caliber was developed in 2007 by ammunition manufacturer Hornady for sport shooting and is known for its high precision.
Broad use of 6.5 mm Creedmoor at USSOCOM
In 2017, SOCOM, after a comparative firing test, chose the cartridge and equipped its existing semi-automatic precision rifles of the M110 and Mk. 20 with corresponding new barrels, while retaining the bolt and magazines. The Department of Homeland Security also followed this decision. In 2019 FN Herstal also introduced a version of the light machine gun Mk 48 (Minimi 7.62) in 6.5 mm Creedmoor for a SOCOM requirement.
In 2020, the Department of Defense then decided to replace the bolt-action Mk 13 Sniper Rifle in the caliber .300 Winchester for mid-range use also with a 6.5 mm semi-automatic rifle with a 20-inch barrel. The British Royal Marines also introduced in 2023 an LMT rifle as the L129 Designated Marksman Rifle in versions for the caliber 7.62 mm NATO with a 16-inch barrel and 6.5 mm Creedmoor with an 18-inch barrel (406 and 457 millimeters).
