Antreg® ARS M4s LW 12.5" AR-15 Semi-Automatic Rifle

The Antreg ARS M4s LW 12.5" is a semi-automatic AR-15 platform rifle featuring a short-stroke piston operating system and a three-position adjustable gas regulator. Equipped with a Lothar Walther barrel in the Light Weight profile, it delivers reduced front-end weight for faster handling without sacrificing durability. Fully ambidextrous controls and a Magpul CTR stock allow the rifle to be easily adapted to different shooters, equipment, and mission requirements.

Short-Stroke Piston System with Adjustable Gas Regulator

Unlike a traditional direct impingement system, the ARS M4s uses a short-stroke piston that keeps combustion gases out of the bolt carrier group, reducing carbon fouling and improving reliability during extended shooting sessions. The three-position gas regulator allows the rifle to be tuned for normal operation, adverse conditions, or suppressor use. The gas block and receiver extension are also engineered to allow the rifle to be fired immediately after being submerged.

Lothar Walther Light Weight Barrel

The 12.5" (317.5 mm) Lothar Walther barrel features the Light Weight profile, reducing front-end weight compared to the Strong profile for quicker handling and improved balance. Both the bore and exterior are salt bath nitrided for enhanced wear and corrosion resistance. The 1:7" twist rate stabilizes the heavier bullet weights commonly used in .223 Rem and 5.56 NATO ammunition.

Free-Float M-LOK Handguard and Fully Ambidextrous Controls

The free-floating M-LOK300 handguard provides a rigid platform for mounting accessories without affecting barrel harmonics, while the full-length top rail accommodates optics and backup sights. The charging handle, safety selector, magazine release, and bolt catch are fully ambidextrous. The safety selector can be configured for either a 60° or 90° throw to match the shooter's preference.

Compact, Durable Construction

Both the upper and lower receivers are precision-machined from AW7075-T6 aluminum alloy and finished with hard-coat anodizing. The rifle features a carbine-length gas system, an Antreg VULCAN M1 muzzle brake, a Magpul CTR adjustable stock, and a Magpul MOE pistol grip with internal storage.

Designed for Practical Use

The gas regulator can be adjusted using the tip of a cartridge, eliminating the need for dedicated tools. The handguard can also be removed without specialized tools for easier maintenance. The ambidextrous charging handle is shaped for positive operation while wearing gloves, and the magazine release is protected against accidental activation.

Benefits You Need to Know:

• short-stroke piston operating system
• three-position adjustable gas regulator
• reduced carbon fouling in the bolt carrier group
• reduced gas blowback toward the shooter's face
• can be fired immediately after submersion
• 12.5" (317.5 mm) Lothar Walther barrel
• Light Weight barrel profile
• 1:7" twist rate
• salt bath nitrided bore and exterior
• free-floating M-LOK300 handguard
• carbine-length gas system
• Antreg VULCAN M1 muzzle brake
• fully ambidextrous controls
• configurable 60° or 90° safety selector
• AW7075-T6 upper and lower receivers
• Magpul CTR stock
• Magpul MOE pistol grip