SIG SAUER MCX SPEAR-LT RMCX-556N-16B-LT-B — Description

The SIG SAUER MCX SPEAR-LT RMCX-556N-16B-LT-B is a premium 5.56 NATO semi-automatic rifle designed as the next evolution of SIG Sauer’s MCX modular rifle platform. Built around a proven short-stroke gas piston operating system, the MCX SPEAR-LT combines advanced reliability, ambidextrous controls, modularity, and a lightweight folding stock configuration for versatile field performance.

The SPEAR-LT features a 16-inch cold hammer forged barrel, lightweight aluminum receiver construction, and a free-floating M-LOK handguard designed for accessory integration. The platform incorporates improvements over previous MCX generations, including a lighter handguard, ambidextrous bolt catch and release, and compatibility with a wide range of MCX components.

This configuration includes a folding stock, black finish, and a 30-round magazine capacity. With its piston-driven action, optics-ready design, SIG flat-blade match trigger, and modular barrel system, the MCX SPEAR-LT provides a modern rifle platform suitable for training, sport shooting, and professional applications.

SIG SAUER MCX SPEAR-LT RMCX-556N-16B-LT-B — Specifications

Manufacturer: SIG SAUER
Model: MCX SPEAR-LT
Model Number: RMCX-556N-16B-LT-B
Caliber: 5.56 NATO (.223 Remington compatible)
Action: Semi-automatic
Operating System: Short-stroke gas piston
Platform: MCX modular rifle system
Barrel Length: 16 inches
Barrel Material: Cold hammer forged carbon steel
Barrel Finish: Nitride finish
Barrel Twist Rate: 1:7″
Receiver Material: Aluminum
Finish: Black finish
Stock: Folding stock with cheek rest
Handguard: Lightweight free-floating M-LOK handguard
Trigger: SIG flat-blade match trigger
Magazine Type: AR-15/STANAG compatible detachable magazine
Magazine Capacity: 30 rounds
Controls: Fully ambidextrous controls
Sights: Optics ready
Muzzle Device: SIG suppressor-ready flash hider
Overall Length: Approx. 34.3 inches
Weight: Approx. 7.4 lbs with magazine

Key Features

• 5.56 NATO chambering for widely available ammunition
• Short-stroke piston system designed for reliable operation and reduced fouling
• 16-inch cold hammer forged barrel for durability and accuracy
• Folding stock design for compact transport and storage
• Fully ambidextrous controls including bolt catch and magazine controls
• SIG flat-blade match trigger for improved trigger performance
• Free-floating M-LOK handguard for accessory mounting
• Modular MCX architecture with interchangeable components
• Optics-ready upper receiver with integrated top rail
• 30-round magazine capacity

Package typically includes:

• SIG SAUER MCX SPEAR-LT 5.56 NATO rifle
• Folding stock assembly
• 30-round magazine (configuration dependent)
• Owner’s manual
• Safety documentation