Orthos Arms Raider S4 Fde 12Ga 18

The Orthos Arms Raider S4 FDE is a modern 12-gauge semi-automatic shotgun engineered for shooters who want tactical functionality without the brutal recoil punishment that comes with magnum loads. Built around a gas-operated system and aluminum receiver, the Raider S4 delivers the kind of reliability and ergonomic refinement you'd expect from a purpose-built combat shotgun, but at a size and weight that works for serious sport shooting, home defense, and field applications. At 18.5 inches with an 18-inch overall length when collapsed, it's nimble enough to maneuver in tight spaces while maintaining the velocity and shot pattern control that make a shotgun work.

What sets the Raider S4 apart is its feature set straight from the box. The patented SHOCK FORCE recoil system is standard and actually delivers on the promise of shooting 3-inch magnum loads without turning your shoulder into a bruise. The adjustable cheek pad lets you dial in your sight picture for your own build and stance, and the FIBERTRON LED front sight—an electro-optic hybrid combining fiber optics with subtle LED illumination—makes target acquisition fast and positive in low light. These aren't upgrades you have to hunt down; they come standard. The furniture comes from a partnership with Black River Manufacturing, and the controls—oversized safety, enhanced bolt release, and advanced charging handle—are designed for gloved operation and intuitive access.

The gun ships with a combat sling, a breacher choke tube for close-quarters work, and magazines tuned for both 3-inch and 2¾-inch ammunition (6+1 capacity with 3-inch, 7+1 with 2¾-inch). The receiver is T6 7075 hardened aluminum, the barrel is 4140 steel with chrome lining, and the finish is Cerakote FDE—a flat dark earth tone that blends function and aesthetics. The angled, modular vertical grip with M-LOK slots lets you configure the gun to your grip preference, and the top Picatinny rail opens the door to optics and accessories. All of this adds up to a shotgun that respects the recoil reality of magnum loads while giving you a modern, configurable platform.

Key Features

• Gas-operated semi-automatic 12-gauge with 18.5-inch barrel
• Patented SHOCK FORCE recoil system for magnum-load comfort
• FIBERTRON LED fiberoptic front sight for fast target acquisition in low light
• Adjustable cheek pad for personalized sight alignment
• Oversized controls (safety, charging handle, bolt release) for tactical operation and gloved use
• T6 7075 hardened aluminum receiver and chrome-lined 4140 steel barrel
• Angled, modular vertical grip with M-LOK rail compatibility
• Top-mounted Picatinny rail for optics and accessories
• Flat dark earth Cerakote finish
• Includes combat sling and breacher choke tube

Specifications

Frequently Asked Questions

What ammunition does the Raider S4 shoot, and how many rounds does it hold?

The Raider S4 is chambered in 3-inch and 2¾-inch 12-gauge ammunition. Magazine capacity is 6+1 (six in the magazine plus one in the chamber) with 3-inch shells, and 7+1 with 2¾-inch shells. The gun comes with a magazine tube configured for both, so you can run either load depending on your needs.

What's included in the box with a new Raider S4?

Your Raider S4 ships with the shotgun itself, a combat sling, the configured magazine tube (rated for both 3-inch and 2¾-inch ammo), a breacher choke tube, the FIBERTRON LED fiberoptic front sight, the adjustable stock with the SHOCK FORCE recoil system, and an owner's manual.

Can I mount an optic or light on the Raider S4?

Yes. The gun features a top-mounted Picatinny rail for optics, and the handguard and grip both include M-LOK slots for lights, lasers, and other accessories. You can also run the factory FIBERTRON LED front sight with a ghost ring rear sight for a traditional sight picture.

How does the SHOCK FORCE recoil system work, and will it really let me shoot magnum loads comfortably?

The SHOCK FORCE recoil system is a patented feature built into the adjustable stock and is designed to absorb recoil impulse so that even 3-inch magnum loads are manageable. The adjustable cheek pad works alongside this system to help you maintain your sight picture and shooting position across different load types.