U.S. Special Operations Command Deploys MK24 Multi-Caliber Rifle Replacing MK17 SCAR-H.

U.S. Special Operations Command is moving to field the MK24 Mid-Range Gas Gun-Assault (MRGG-A), a new rifle designed to extend engagement range, improve accuracy, and give special operations forces greater flexibility across diverse combat environments. The development will replace the long-serving MK17 SCAR-H and reflects SOCOM’s effort to maintain an operational advantage against increasingly capable adversaries on modern battlefields.

The MK24 is intended to deliver more precise fire at longer distances while preserving the versatility required for missions ranging from direct action raids to distributed operations. Its introduction aligns with a broader trend toward enhancing lethality, survivability, and effectiveness at extended ranges as special operations forces prepare for future high-intensity conflicts.

Related News: US Special Forces launches HICAR hypervelocity ammunition program to double M4 carbine range

MK24 Mid-Range Gas Gun-Assault (MRGG-A) rifle developed by LMT Defense for U.S. Special Operations Command. The multi-caliber weapon can be converted between 7.62×51 mm NATO and 6.5 mm Creedmoor configurations using a quick-change barrel system. (Picture source: Lmt Defense)

This transition is part of SOCOM’s ongoing efforts to adapt its small-arms inventory to evolving battlefield requirements. While the MK17 already offered greater range and stopping power than standard 5.56 mm rifles, operational experience gradually highlighted the need for a system capable of delivering improved long-range performance while maintaining versatility and limiting the logistical burden on deployed units.

According to information published by Task & Purpose on May 26, 2026, citing comments from SOCOM spokesperson Navy Cmdr. Joe Vermette, the MK24 is currently in production and is intended to serve as a direct replacement for the MK17. Vermette stated that initial deliveries are expected during the current fiscal year and that multiple SOF components will receive the new rifle through an accelerated fielding process.

The MK24 is manufactured by LMT Defense under the Mid-Range Gas Gun-Assault program, which was developed to provide special operations personnel with a weapon capable of addressing both close-range and extended-range engagements. In August 2025, the company received a 10-year indefinite-delivery/indefinite-quantity contract valued at up to $92 million. The contract covers weapon kits, spare parts, accessories, user training, and future engineering modifications.

One of the MK24’s most notable features is its multi-caliber architecture. The rifle incorporates a quick-change barrel mechanism that allows operators to switch between 7.62×51 mm NATO and 6.5 mm Creedmoor ammunition. This capability gives units additional flexibility to adapt their weapon configuration to mission requirements without relying on multiple weapon families. For special operations forces, which often operate with limited logistical support, such modularity can provide practical advantages.

Several technical characteristics distinguish the MK24 from its predecessor. The publicly displayed configuration is equipped with a 14.5-inch barrel and weighs approximately 9.2 pounds (4.2 kilograms) without a magazine or accessories. The rifle also features fully ambidextrous controls and a monolithic upper receiver, which increases structural rigidity and contributes to maintaining accuracy. LMT Defense has retained ergonomics similar to those of the M4 carbine, facilitating transition and reducing training requirements for operators already familiar with that weapon family.

A 2023 presentation video released by Geissele Automatics provides a closer look at the company's Mid-Range Gas Gun-Sniper (MRGG-S) rifle and its intended operational role.

The adoption of the 6.5 mm Creedmoor cartridge is one of the key aspects of the program. According to SOCOM officials, this ammunition enables effective engagements beyond 1,200 meters while generating less recoil than the MK17. The projectile retains velocity and energy more effectively at long distances than conventional 7.62 mm NATO ammunition, increasing the probability of first-round hits against distant targets. These characteristics have contributed to growing military interest in the caliber for missions requiring extended-range capabilities without relying on heavier precision weapon systems.

In operational terms, the MK24 occupies a position between a conventional assault rifle and a dedicated precision weapon. During urban operations or short-range engagements, operators can employ the 7.62 mm NATO configuration to maximize terminal effects and barrier penetration. In desert, mountainous, or open terrain, the 6.5 mm Creedmoor option provides greater range and improved first-round hit probability. This approach allows small special operations teams to field a single weapon capable of covering multiple tactical scenarios while reducing the need to carry additional specialized firearms. SOCOM officials have consistently highlighted the rifle’s accuracy, adaptability, and suitability for dispersed operations.

The MK24 also benefits from experience gained through the MK24 Mid-Range Gas Gun-Sniper variant, which entered service in 2023. Lessons derived from that system appear to have contributed to the development of the assault configuration now selected by SOCOM. This continuity simplifies training, maintenance, and logistical support while supporting a faster fielding timeline.

Beyond its impact on U.S. special operations forces, the adoption of the MK24 may influence future small-arms modernization programs among allied countries. Several NATO members are currently reassessing caliber requirements and infantry weapon systems in light of lessons learned from recent conflicts, where range, survivability, and ballistic effectiveness have received renewed attention. If the MK24 performs as expected in service, its multi-caliber concept could inform future capability decisions within the Alliance and contribute to broader interest in weapon systems designed to adapt to a wider range of operational requirements.

Written By Erwan Halna du Fretay - Defense Analyst, Army Recognition Group
Erwan Halna du Fretay holds a Master’s degree in International Relations and has experience studying conflicts and global arms transfers. His research interests lie in security and strategic studies, particularly the dynamics of the defense industry, the evolution of military technologies, and the strategic transformation of armed forces.