Breaking News
SIG Sauer redesigns M250A1 6.8 mm machine gun for easier handling by U.S. Army soldiers.
SIG Sauer unveiled the M250A1 light machine gun at AUSA 2026 in Washington, D.C., introducing a redesigned 330 mm barrel configuration alongside structural and ergonomic modifications to the U.S. Army's Next Generation Squad Weapon variant. The 18.75 percent reduction in barrel length improves maneuverability and reduces front-end weapon weight while retaining compatibility with standard 6.8×51 mm hybrid ammunition. Mechanical updates, including an insulated quick-change barrel handle, a captive forearm cover, and reinforced receiver cross-bolts, directly address carbon accumulation and receiver wear reported during initial operational evaluations.
The M250A1 features a shorter 330 mm barrel for easier handling, a quick-change barrel handle for faster replacement during firing, a modified gas system to reduce carbon buildup, and reinforced components to improve durability and reliability. (Picture source: Army Recognition)
On October 12, 2026, SIG Sauer unveiled the M250A1 at AUSA 2026 in Washington, D.C., introducing a revised version of the U.S. Army's new M250 6.8×51 mm light machine gun with a shorter barrel, reinforced receiver, and modified gas system. Its new 330 mm barrel replaces the 406 mm variant currently entering service, which represents a length reduction of 18.75%, while its reduced external diameter removes additional weight from the front of the weapon. Jason St. John, SIG Sauer's senior director of strategic products, confirmed to Howard Altman that the U.S. Army will continue purchasing both barrel lengths, while retaining the existing ammunition despite the lower muzzle velocity produced by the shorter configuration. Other modifications include an insulated quick-change barrel handle, captive forearm cover, revised buttstock, enlarged trigger guard, and reinforced tripod interfaces. The original M250 received Type Classification-Standard in May 2025, but the M250A1 remains subject to formal Army acceptance.
The M250A1's smaller barrel is 115 mm (25.8%) shorter than the 445 mm length originally anticipated under the Next Generation Squad Weapon (NGSW) program, and 76 mm shorter than the current 406 mm barrel. SIG Sauer has also tapered the barrel to save weight, although the complete M250A1 mass remains undisclosed. The original M250 weighs 5.9 kg unloaded without optics or suppressor, establishing the baseline for comparison. The shorter barrel matches the original M7 rifle's nominal barrel length, while the retained 406 mm option provides 23% more distance for propellant gases to accelerate the projectile. The Army considers both configurations compatible with its lethality requirements, but measured differences in muzzle velocity, dispersion, and penetration at 600 m and 800 m have not been established.
The mechanical redesign principally concerns barrel replacement, carbon accumulation, and structural wear encountered during M250 handling and training. Unlike the original M250, the M250A1 incorporates an insulated barrel handle, like the M249's conventional quick-change system, and a captive forearm cover adapted from SIG Sauer's .338 Norma Magnum machine gun, preventing loose components during barrel changes. A funnel-shaped guide simplifies the alignment of the gas piston when reinstalling the barrel, while revised gas-system components reduce exposure to carbon deposits. SIG Sauer also enlarged the trigger guard for Arctic gloves, and a different commercially available Magpul buttstock replaces the original following soldier evaluations.
Receiver cross-bolts and a saddle-screw mounting arrangement redistribute firing vibrations that previously concentrated wear between steel fasteners and the aluminum receiver during tripod and vehicle-pintle employment. The effect of these modifications on service life has not yet been quantified in firing cycles or rounds. The original M250 is an open-bolt, gas-piston-operated, belt-fed machine gun with safe, semiautomatic, and fully automatic settings and a two-position gas regulator. Its nominal cyclic rate is 800 rounds per minute, equivalent to 13.3 rounds per second during uninterrupted automatic fire, although this does not represent its sustained-fire rate. The standard Army configuration weighs 5.9 kg without its suppressor and 6.58 kg with it, while overall length increases from 933 mm to 1,064 mm when suppressed. Existing barrel options include 343 mm, 406 mm, 457 mm, and 508 mm, with cold-hammer-forged steel construction and a 1:7-inch rifling twist.
The weapon feeds from 50-round or 100-round belt carriers, measures 298 mm high and 234 mm wide with its bipod, and incorporates a hard-coat-anodized aluminum receiver, a folding feed cover, M-LOK interfaces, and an extended Picatinny rail for the XM157 fire-control system. Its mounting interfaces accommodate existing M249, M240, and FN MAG tripod and vehicle arrangements. The M250 fires a 6.8×51 mm hybrid cartridge with a brass body and steel base, operating in the mid-70,000 psi pressure range, with certain configurations approaching 80,000 psi. Its case has a stated design potential of 125,000 psi, representing a 50,000 psi (66.7%) margin against a 75,000 psi reference, but the Army has not authorized higher-pressure ammunition. Selected 6.8 mm ammunition and barrel combinations can approach or exceed 900 m/s, although no muzzle velocity has been established for the M250A1's 330 mm barrel.
Ammunition weight is another significant difference from the M249. A 100-round 6.8 mm belt pouch weighs 3.07 kg, compared with 3.14 kg for a 200-round 5.56 mm belt and drum. Consequently, 400 rounds of 6.8 mm weigh 12.28 kg, while 600 rounds of 5.56 mm weigh 9.42 kg, leaving the M250 ammunition load 2.86 kg heavier despite containing 200 fewer cartridges. The M250 replaces the M249 Squad Automatic Weapon, a 5.56×45 mm machine gun introduced in 1984, which weighs 7.5 kg unloaded, measures 1,036 mm long, and uses a 465 mm barrel. The M249 fires 750 to 850 rounds per minute, with sustained and rapid rates of 85 and 200 rounds per minute, and effective ranges of 600 m against point targets and 800 m against area targets. The original M250 is 1.6 kg (21.2%) lighter when unsuppressed, but the difference falls to 0.92 kg with its suppressor installed.
Including ammunition reverses the comparison: an M249 with 600 rounds weighs 16.92 kg, whereas a suppressed M250 with 400 rounds weighs 18.86 kg, excluding optics and accessories. The latter is subsequently 1.94 kg heavier while carrying one-third fewer cartridges. The 6.8 mm cartridge is intended to improve effectiveness against protected targets and extend useful engagement distances, but the operational comparison depends on hits and target defeat rather than cartridge caliber alone, making the new hot-barrel handling mechanism particularly relevant to the Army's acceptance process. The M250A1 is being developed under the NGSW program, awarded to SIG Sauer on April 19, 2022, with an initial $20.4 million production contract and a ten-year ceiling of $4.7 billion. The selection followed 27 months of evaluation involving more than 500 military personnel and 20,000 testing hours, with initial production covering 25 XM5 rifles and 15 XM250 automatic rifles.
Original Army planning anticipated 107,000 rifles and 13,000 automatic rifles for close-combat formations. The FY2026 procurement request included 16,154 M7 rifles, 2,636 M250s, and 19,524 M157 fire control systems, representing 18,790 weapons and one M250 per 6.13 rifles. Initial fielding began with the 101st Airborne Division in 2024, followed by standard classification in May 2025 and M250 training for Minnesota's 34th Infantry Division in September 2025, extending fielding into the Army National Guard. The M250A1's development also follows the same pattern as the M7's evolution into the shorter M8 carbine, with the Army accepting substantial dimensional and mechanical changes after initial fielding. However, the M250A1 has not received formal acceptance, and no confirmed procurement quantity, conversion schedule for existing M250s, or revised unit price has been established.
Explore More Defense News
• Land Defense News
• Naval Defense News
• Defense Aerospace News
Written by Jérôme Brahy
Jérôme Brahy is a defense analyst and documentalist at Army Recognition. He specializes in naval modernization, aviation, drones, armored vehicles, and artillery, with a focus on strategic developments in the United States, China, Ukraine, Russia, South Korea, Türkiye, and Belgium. His analyses go beyond the facts, providing context, identifying key actors, and explaining why defense news matters on a global scale.