The Orthos Arms Raider S4 is a semi-automatic shotgun chambered in 12 Gauge with an 18.5-inch barrel and a 6+1 round capacity. It has an OD Green finish and an M-LOK compatible handguard for accessory attachment. 
 

Key Specifications 

• Brand: Orthos Arms 
• Model: Raider S4 
• Caliber: 12 Gauge 
• Action: Semi Auto 
• Capacity: 6+1 rounds 
• Barrel Length: 18.5 inches 
• Color/Finish: OD Green 
   

Detailed Features 

• Semi-automatic action in 12 Gauge 
• 18.5-inch barrel in a tactical configuration 
• M-LOK handguard for accessory mounting 
• OD Green finish throughout 
• 6+1 round capacity

Owners of the Raider S4 tend to highlight the M-LOK handguard as a practical feature, making it easy to run a light or foregrip without add-on adapters. The OD Green finish gets generally positive feedback for durability and appearance.

The semi-auto action is where opinion splits. Some owners report running a variety of loads without issue from the start, while others note the Raider S4 needs a break-in period before it cycles reliably across different shell weights.

At its price point in the tactical shotgun category, the Orthos Arms name is less established than some competitors, and a few owners mention limited aftermarket support. Those who have run it hard tend to come away satisfied with the build quality.