SIG Sauer XM8 Carbine

SIG Sauer · Carbine · In Service · 2026

Also known as: XM8

Overview

The XM8 Carbine is a compact 6.8x51mm select-fire carbine delivered to the US Army by SIG Sauer in April 2026 for the Close Combat Force. It shortens the M7 rifle's barrel from 13 to 11 inches and drops overall length to just over 32 inches and weight to about 7.3 pounds, while retaining the M7's short-stroke gas piston action, ambidextrous controls, folding stock and compatibility with the M157 fire control and the Army's 6.8 mm ammunition.

Specifications

Weight (empty)3325 g (117.3 oz)
Overall Length813 mm (32.01")
Barrel Length279 mm (10.98")
Action TypeGas Operated Short Stroke
Firing MechanismRotating Bolt
Trigger TypeSingle Stage
Magazine Capacity20 rounds
Magazine TypeDetachable Box
Muzzle Velocity869 m/s (2851 fps)
Effective Range600 m (656 yd)
Rate of Fire700 rpm
Barrel RiflingRight Hand
Frame MaterialAluminum
Barrel MaterialSteel
Stock MaterialPolymer
FinishCoyote Brown

Calibers

Features

Base model

Sig-Mcx-Spear

Service history

Operators

Production

Production years: 2026-present

14,944 carbines planned for procurement through FY2027

Origin

Country of origin: United States

Notes

The XM8 designation is recycled from the cancelled 2000s Heckler & Koch XM8 programme and is unrelated to it. Procurement of 14,944 carbines was planned through FY2027.

Background

The Army had already burned the XM8 name once, on a Heckler & Koch rifle cancelled in 2005 after years of controversy. Two decades later it reused the designation for the SIG carbine replacing the M4A1.