The Mossberg 590S Shockwave is a pump-action 12-gauge with a 14.375-inch barrel, Raptor birdshead grip, and 8+1 capacity. At 30.75 inches overall and 5.3 lbs, it's compact and maneuverable. The 590S designation means it can cycle 1.75-inch mini shells, 2.75-inch standard shells, and 3-inch magnum shells without adapters. 
 

Key Specifications 

• Manufacturer: Mossberg 
• Model: 590S Shockwave 
• Action Type: Pump 
• Caliber: 12 Gauge 
• Barrel Length: 14.375 inches 
• Chamber Size: 3 inches 
• Capacity: 8+1 rounds (also supports configurations of 5+1 and 4+1) 
• Overall Length: 30.75 inches 
• Weight: 5.3 lbs 
• Stock/Grip Type: Raptor Birdshead Grip 
• Sights Type: Bead Front 
• Finish Color: Black Anodized 
• Condition: New in Box 
   

Detailed Features 

1. Compact Design: At 14.375 inches of barrel and 30.75 inches overall, it maneuvers in tight spaces. 
2. High Capacity: 8+1 rounds on full-size shells. 
3. Raptor Birdshead Grip: Improves control compared to a pistol grip and gives the Shockwave its distinctive profile. 
4. Black Anodized Finish: Corrosion-resistant and durable. 
5. Multi-shell Compatibility: The 590S cycling design handles all three common shell lengths without modification. 
    

Usage Scenarios 

1. Home Defense: Compact enough for hallways and tight spaces, with serious firepower on tap. 
2. Recreational Shooting: The unusual configuration and fun factor make it popular at the range. 
3. Field Use: Lightweight for its capacity; works for close-range small game with appropriate loads.

The 590S Shockwave gets a mostly positive reception, with some consistent caveats that potential buyers should weigh.

The compact size and light weight are the most praised qualities. Owners who need something maneuverable for home defense or vehicle storage find the 30.75-inch overall length very practical. The birdshead Raptor grip improves handling over a standard pistol grip, and most owners adjust to it quickly. Reliability with various ammunition types is generally well-rated, consistent with Mossberg's reputation.

The recoil is real and comes up regularly. Without a stock to distribute the force, 12-gauge loads hit harder than the same shell fired from a full-stock shotgun. Most owners recommend starting with lighter loads. Some also note that the 590S designation's multi-shell compatibility is genuinely useful and sets this model apart. Customization with lights or slings is possible and discussed frequently, though some modifications can create legal complications in certain jurisdictions - worth researching before adding accessories.