M7 rifle

The M7 rifle, previously designated as XM7 and originally as XM5, is the U.S. Army's adopted variant of the SIG MCX-SPEAR chambered in 6.8×51mm Common Cartridge (.277 Fury), designed by SIG Sauer for the Next Generation Squad Weapon (NGSW) program in 2022 to replace the M4 carbine.

The M7 features a gas-operated system, a free-floating reinforced M-LOK handguard for direct accessory attachment to slotted hole mounting points, and uses SR-25 pattern magazines. It was fielded beginning in March 2024.

History

In January 2019, the United States Army began the Next Generation Squad Weapon Program to find replacements for the M4 carbine and M249 Squad Automatic Weapon. In September 2019, SIG Sauer submitted its designs. The SIG MCX-SPEAR (the rifle's commercial designation) chambered in .277 Fury (later designated as the "6.8 Common Cartridge" after Army acceptance) in response to concerns that improvements in body armor would diminish the effectiveness of calibers such as 5.56×45mm NATO (for the M4A1 and M249 SAW) and 7.62×51mm NATO (for the M240).

In April 2022, the Army awarded a ten-year contract to SIG Sauer to produce the M7 rifle, and the M250 light machine gun, to replace the M4 carbine and M249 Squad Automatic Weapon, respectively. The rifle was originally designated as the XM5, continuing the numerical sequence from the M4 carbine it is set to replace. In January 2023, the Army changed the name of the rifle from the XM5 to the XM7, to avoid a trademark conflict with Colt's M5 carbine.

The first batch of 25 XM7 rifles and 15 XM250 light machine guns were planned for delivery in late 2023. The Army may order 107,000 rifles and 13,000 light machine guns over the next decade for close combat forces, including infantry, cavalry scouts, combat engineers, forward observers, and combat medics. There are no current plans to issue the XM7 and XM250 to non-close combat soldiers. The contract does have the option to build additional XM7 rifles and XM250 light machine guns should the U.S. Marine Corps and U.S. Special Operations Command choose to be included in the adoption.

In September 2023, XM7 rifles were delivered to the 101st Airborne Division and 75th Ranger Regiment for user tests. Operational testing of the XM7 rifle, XM250 light machine gun, and XM157 Fire Control Optic was scheduled to begin in 2024, but widespread distribution was not assured. In March 2024, 1st Battalion, 506th Infantry Regiment of the 101st Airborne Division began fielding the XM7. In January 2026, the U.S. Army's 25th Infantry Division were trained with the M7 rifle.

In May 2025, the XM7 was type classified as the M7 rifle. The Type Classification confirms the system meets the U.S. Army's stringent standards for operational performance, safety, and sustainment.

In September 2025, SIG Sauer introduced an improved carbine variant of the M7 rifle. The U.S. Army decided to proceed with the procurement of the M7 carbine design in December 2025, designating it as the XM8 carbine.

Design details

The M7 was developed for the 6.8×51mm Common Cartridge, offering greater lethality at longer ranges. To fully utilize its capabilities, it is paired with the M157 Fire Control optic, which integrates a laser rangefinder, ballistic calculator, and other technologies to increase accuracy. The M7 is the first U.S. Army service rifle to be issued with a suppressor as standard to reduce its firing signature. The original suppressor was 7 in (180 mm) long and weighed 1.46 lb (0.66 kg).

The rifle weighs 8.38 lb (3.80 kg), or 9.84 lb (4.46 kg) with a suppressor. It uses SR-25 pattern magazines that hold either 20 or 25 rounds in a detachable box magazine. The proposed combat ammunition load for each soldier will be 140 total rounds in seven 20-round magazines, in total weighing 9.8 lb (4.4 kg).

Compared to the M4A1 carbine weighing 6.34 lb (2.88 kg) unsuppressed, with a basic combat load of 210 rounds in seven 30-round magazines, in total weighing 7.4 lb (3.4 kg), the M7 rifle weighs about 2 lb (0.91 kg) more. Each soldier carries roughly a 4 lb (1.8 kg) heavier load with 70 fewer rounds.

Variants

In October 2025, SIG Sauer displayed the (Product Improvement Effort) PIE M7 and M7 carbine at the Association of the United States Army (AUSA) Annual Meeting & Exposition. The PIE M7 variant has a 13.5 in (340 mm) barrel and has been lightened by approximately 0.7 lb (0.32 kg), from roughly 8.3 lb (3.8 kg) to about 7.6 lb (3.4 kg). The M7 carbine variant has a 10 in (250 mm) barrel and weighed about 7.3 lb (3.3 kg). These weights are reported as baseline figures, excluding any optical sight or suppressor. The weight reduction was achieved through a redesigned upper receiver, a slimmer barrel profile, lighter internal components, and removal of the folding stock hinge.

The SLX suppressor was also shortened and paired with a new lightweight thermal shield, which delays the visible heat signature under night-vision and thermal optics until after roughly 100 rounds, rather than about 40 rounds without the thermal shield.

U.S. Army officials are reviewing whether to field the standard-length PIE M7, adopt the shorter carbine variant as the new standard, or issue different configurations to different unit types.

XM8 carbine

SIG Sauer presented an improved carbine variant of the M7 rifle at Defence and Security Equipment International (DSEI) 2025. It is lighter and more compact than the original design, with a reported 10.5-inch barrel instead of 13.5 inches, lightened internal parts, and a reprofiled handguard. It weighs about 7.5 lb (3.4 kg) unloaded, without an optical sight but with a suppressor, compared to about 9.84 lb (4.46 kg) for the original M7. SIG Sauer reported that muzzle velocity with the shorter barrel is about 2,800–2,900 feet per second, a slight reduction from roughly 3,000 feet per second. The M7 carbine variant was later designated as the XM8 carbine, which is unrelated to the Heckler & Koch XM8. In April 2026, the U.S. Army has accepted the first delivery of XM8 carbines from Sig Sauer.

The XM8 carbine is a shortened and improved variant of the M7 rifle developed under the Next Generation Squad Weapons program. The carbine variant was introduced in response to soldier feedback calling for a lighter and more maneuverable rifle. The XM8 is designed to improve mobility and adaptability across different operational environments while maintaining the performance and reliability standards of the M7 platform.

The XM8 has a barrel length of 11 in (280 mm) and an overall length of approximately 32.79 in (833 mm) with the stock collapsed and suppressor attached. It weighs about 7.3 lb (3.3 kg) unloaded and 8.8 lb (4 kg) with the improved suppressor. Compared to the standard M7 rifle, the XM8 is approximately 3.5 in (89 mm) shorter and more than 1 lb (0.45 kg) lighter, with the same weight as an M4A1 carbine. It is supported by ongoing NGSW product improvements, including the introduction of 25-round magazines as standard, lighter ammunition to increase soldier load capacity, a redesigned suppressor with heat shield that has a reduced length of 6 in (150 mm) and weighs 1.31 lb (0.59 kg), alternate optics, and enhancements to the M157 fire control system to create target reference points and request for fire support with greater precision.

Gallery

U.S. Army infantryman with an M7 rifle
U.S. Army infantryman firing an M7 rifle
U.S. Army infantryman firing an M7 rifle with M157 fire control optic
U.S. Army infantryman training with an M7 rifle at Schofield Barracks
U.S. Army infantryman firing an M7 rifle during a weapon qualification

Users

United States: Used by the United States Army.