SIG SAUER MCX-SPEAR LT 7.62x39mm Rifle

Description

SIG SAUER MCX-SPEAR LT 7.62x39mm Rifle

The SIG SAUER MCX-SPEAR LT combines the modular MCX platform with the familiar ballistic performance and broad ammunition availability of the 7.62x39mm cartridge. This semi-automatic rifle features a 16-inch cold-hammer-forged barrel, coyote-anodized aluminum receivers, a folding and adjustable stock, and one 28-round magazine. Its short-stroke gas-piston operating system keeps the action independent of a conventional AR-style buffer tube, allowing the stock to fold against the receiver for more compact storage and transport.

As the third generation of the MCX family, the SPEAR-LT incorporates design lessons from the original MCX and MCX Virtus. The platform uses a lightweight aluminum handguard, ambidextrous controls, an AR-style lower-receiver layout, and a modular barrel and handguard system. The result is a rifle that feels familiar to users of modern sporting rifles while offering a distinct operating system and extensive configuration flexibility.

Short-Stroke Piston Operation

The MCX-SPEAR LT is a magazine-fed, gas-operated rifle that fires from a rotating, closed bolt. A short-stroke piston drives the operating group, and the 7.62x39mm configuration uses a caliber-specific piston and two-position gas valve. This design is engineered to support reliable cycling under varied operating conditions while keeping combustion gas concentrated toward the front of the firearm rather than routing it directly into the receiver.

The 16-inch carbon-steel barrel uses a 1:9.5-inch twist rate and is threaded 5/8×24 at the muzzle. A factory three-prong flash hider helps reduce visible muzzle flash and is compatible with the appropriate SIG SAUER quick-detach suppressor interface. Suppressor ownership and use are regulated, and customers must confirm device compatibility and comply with all federal, state, and local requirements.

Modular Handguard and Optics-Ready Upper

A lightweight 13-inch aluminum handguard surrounds the barrel and provides M-LOK attachment slots along the sides and bottom. A continuous M1913 Picatinny top rail extends across the upper receiver and handguard for mounting a compatible optic, backup sights, or other approved equipment. The rifle ships without fixed sights, allowing the owner to select a red dot, prism sight, low-power variable optic, or other sighting system that fits the intended role.

The handguard and barrel are removable according to the MCX-SPEAR LT operator’s manual, supporting maintenance and properly configured component changes. Any caliber or barrel conversion requires the correct SIG SAUER parts, bolt and magazine compatibility, headspace considerations, and adherence to barrel-length laws. Owners should follow the factory manual or use a qualified armorer rather than treating modularity as permission for improvised combinations.

Ambidextrous Controls and Folding Stock

Fully ambidextrous controls include the safety selector, magazine release, bolt catch, and bolt release, making the rifle adaptable to right- or left-handed operation. The flat-blade match trigger provides a consistent interface for deliberate shooting. A folding, adjustable stock with cheek rest mounts to the rear 1913 interface and can be configured for the shooter’s length of pull and optic height.

Because the action does not require a receiver extension, the stock can fold without preventing the mechanism from cycling. Always follow the operator’s manual concerning safe stock position, firing practices, and inspection. The rifle measures approximately 34.3 to 34.5 inches with the stock extended and weighs about 7.6 pounds before accessories, depending on the measurement source and installed magazine.

Key Specifications

• Caliber: 7.62x39mm.
• Action: Semi-automatic short-stroke gas piston with rotating closed bolt.
• Barrel: 16-inch cold-hammer-forged carbon-steel barrel.
• Twist rate: 1:9.5 inches.
• Muzzle thread: 5/8×24 with a factory three-prong flash hider.
• Capacity: 28+1 rounds; one 28-round magazine included.
• Handguard: 13-inch lightweight aluminum M-LOK handguard.
• Top rail: Continuous M1913 Picatinny interface; optic ready.
• Controls: Fully ambidextrous safety, magazine release, and bolt controls.
• Trigger: SIG flat-blade match trigger.
• Stock: Folding and adjustable stock with cheek rest.
• Finish: Coyote anodized.
• Identification: MPN RMCX-762R-16B-LT; UPC 798681660889.

Configured for Modern Rifle Use

The MCX-SPEAR LT 7.62x39mm is suited to customers seeking a premium piston rifle with folding-stock portability, modern accessory support, and a cartridge commonly used for sporting and defensive applications. Before use, clean and inspect the rifle, install and zero a suitable sight, confirm magazine and ammunition function, and become familiar with the gas valve and ambidextrous controls. All ownership, magazine use, transport, and configuration changes must comply with applicable law.