The Mossberg 590A1 is a pump-action 12-gauge with an 18.5-inch heavy-walled barrel, 6+1 capacity, and ghost ring sights. It weighs 7 lbs, measures 39.5 inches overall, and has a black synthetic stock with a parkerized finish. 
 

Key Specifications: 

• Brand: Mossberg 
• Model: 590A1 
• Caliber/Gauge: 12 Gauge 
• Action Type: Pump Action 
• Barrel Length: 18.5 inches 
• Chamber Size: 3 inches 
• Capacity: 6+1 rounds 
• Weight: 7 lbs  
• Overall Length (OAL): 39.5 inches  
• Sights: Ghost Ring  
• Stock Material: Synthetic (Black Finish) 
   

Features 

The heavy-walled barrel is stiffer than standard shotgun barrels, which reduces flex during firing and contributes to durability over a high round count. Ghost ring sights provide a fast, clear sight picture in low-light conditions — a meaningful advantage over bead-only setups. The M-Lok forend accepts lights, grips, and other accessories without replacing the factory furniture. 
 
The parkerized finish handles moisture and field use without showing wear quickly. At 7 lbs the gun is manageable in confined spaces while remaining stable under recoil.

Owners consistently praise the 590A1 for its reliability. Cycling different ammunition types without issues is the most repeated positive note. The heavy-wall barrel and parkerized finish get credit for durability under hard use, and the 18.5-inch barrel is called out as a practical length for home defense situations.

The action is widely described as smooth, and the ghost ring sights are preferred over basic bead sights for defensive use. Weight is the primary complaint — at 7 lbs some owners find it tiring during extended carry or drills. A few reviewers mention preferring semi-auto platforms for ease of use. Overall feedback leans strongly positive for reliability and build quality, with weight and user-friendliness the main trade-offs.