The LMT MARS-L 16″ 5.56 Quad Rail Rifle is a semi-automatic 5.56 NATO / .223 Remington rifle built around Lewis Machine & Tool’s Monolithic Rail Platform (MRP). The upper receiver is machined from a single aerospace-grade aluminum forging and features LMT’s quick-change barrel system, allowing compatible barrel assemblies to be installed or removed using two locking bolts. This model includes a 16.1-inch chrome-lined barrel with a 1:7 right-hand twist, a direct impingement operating system, and a full-length 1913 Picatinny quad rail for mounting optics and accessories.

The MARS-L ambidextrous lower receiver provides ambidextrous controls for the safety selector, bolt catch, and magazine release, making the rifle adaptable for both right- and left-handed shooters. Additional features include an LMT SOPMOD stock, textured ergonomic pistol grip, low-profile gas block, and straight gas tube. The rifle ships with one magazine, three rail panels, and an owner’s manual, making it ready for a variety of sporting, training, and professional applications.

Specifications

• Caliber: 5.56 NATO / .223 Remington
• Operating System: Direct Impingement
• Barrel Length: 16.1 in
• Barrel Material: Chrome-Lined Steel
• Twist Rate: 1:7 RH
• Upper Receiver: Monolithic Rail Platform (MRP)
• Rail System: Full-Length 1913 Picatinny Quad Rail
• Lower Receiver: MARS-L Fully Ambidextrous
• Bolt Carrier Group: Semi-Auto
• Gas Block: Low Profile
• Gas System: Straight Gas Tube
• Stock: LMT SOPMOD
• Grip: LMT Textured Ergonomic Grip

Features

• Monolithic Rail Platform (MRP) upper receiver machined from a single aluminum forging
• Quick-change barrel system compatible with LMT barrel assemblies
• 16-inch chrome-lined barrel with 1:7 twist
• Full-length Picatinny quad rail for optics and accessories
• Fully ambidextrous MARS-L lower receiver controls
• Low-profile gas block and straight gas tube
• Proprietary barrel coating with cryogenic treatment
• Includes one magazine, three rail panels, and owner’s manual

At a glance