The Mossberg 590S Tactical is a 12-gauge pump-action shotgun with a 20-inch barrel and a 13-round capacity when loaded with 1.75-inch minishells. The 590S designation indicates the gun is engineered to cycle minishells, standard 2.75-inch loads, and 3-inch shells from the same magazine tube without modification. 
 

Key Specifications 

• Brand: Mossberg 
• Model: 590S Tactical 
• Action: Pump Action 
• Gauge: 12 GA 
• Chamber: 3" 
• Barrel Length: 20" 
• Capacity: 13 rounds (1.75") 
• Weight: 7.25 lbs 
• Finish: Matte Black 
   

Detailed Features 

 
The 20-inch barrel is two inches longer than the short-barreled version, which adds some velocity and makes the gun a better fit for users who want slightly more reach. The 13-round minishell capacity is the key differentiator of the 590S platform, delivering more rounds in the magazine tube than any standard 12-gauge pump at this barrel length. The bead front sight provides basic aiming for close-range work. The ambidextrous top-tang safety is simple to operate with the thumb of either hand. The matte black finish resists reflection and is low-maintenance. 
 

Target Audience 

 
Home defense shotgun buyers who want maximum round count in a reliable pump-action platform. Tactical competitors who need a high-capacity pump for competition courses. Law enforcement and security professionals who value simplicity and reliability. 
 

Usage Scenarios 

 
Home defense with minishells gives the user 13 rounds before a reload is needed, which substantially extends the available firepower in a single-story home situation. The 20-inch barrel is manageable indoors while providing a bit more velocity than the 18.5-inch version. Customization with lights, side-saddles, and optics is well-supported given Mossberg's accessory ecosystem.

The Mossberg 590S Tactical in the 20-inch configuration gets positive reviews centered on its high capacity and reliable pump-action function. The 13-round capacity with minishells is the feature most commonly highlighted by home defense buyers, who value having more rounds available without reloading.

Reliability is a consistent theme. The pump action cycles without complaint across standard loads, and most owners report clean function with both minishells and full-size ammunition. Mossberg's overall reliability reputation reinforces buyer confidence in the platform.

Versatility is mentioned frequently. Owners appreciate that the gun works for home defense, competitive shooting, and recreational shooting without modification, and the accessory ecosystem makes customization straightforward.

Weight and maneuverability draw some critique. At 7.25 lbs the gun is not light, and users comparing it to semi-automatic shotguns note the weight difference during active competition stages. Recoil with standard 12-gauge loads is noted as something to manage, particularly for newer shooters.

Pricing discussions are mixed. Most buyers consider the capacity and reliability combination to represent fair market value, while others note that similarly capable alternatives are available in a comparable price range.