The Mossberg 940 Pro JM is a 12-gauge semi-auto shotgun with a 24-inch vented rib barrel, matte blued finish, and adjustable synthetic stock. It holds 4+1 rounds of 3-inch shells, weighs 7.75 lbs, and measures 45.5 inches overall. A Briley extended choke set (IC, C, Mod) is included. 
 

Key Specifications: 

• Manufacturer: Mossberg 
• Model: 940 Pro JM 
• Caliber/Gauge: 12 GA 
• Barrel Length: 24 inches (Vent Rib) 
• Overall Length: 45.5 inches 
• Capacity: 4+1 rounds 
• Chamber Size: 3 inches 
• Weight: 7.75 lbs 
• Finish: Matte Blued (Black) 
• Stock: Synthetic, Adjustable LOP 
• Sights: Fiber Optic Front (Fixed) 
• Chokes: Briley Extended Set (IC, C, Mod) 
• Safety: Two-position Thumb Safety 
   

Detailed Features: 

The enlarged and beveled loading port speeds up reloads under pressure. The oversized charging handle is easy to grab with gloves or in poor conditions. The elongated pinch-free elevator feeds shells smoothly and reduces handling issues during operation. The adjustable LOP stock fits different-sized shooters and contributes to better control during strings of fire. The Briley choke set covers a practical range of applications from close birds to longer crossing shots. 
 

Usage Scenarios: 

The 940 Pro JM is built for competitive shotgun sports where fast reloads and reliable cycling are critical. The competition-oriented features (loading port, charging handle, elevator) translate directly to practical improvements in stages. It also works for hunting and home defense, where the same reliability and ease of use apply outside of a competition context.

The Mossberg 940 Pro JM gets consistently positive marks from owners, particularly those who use it in competitive shooting. Reliable cycling is the most common positive. The semi-auto action handles varied loads cleanly and maintains its rhythm under extended use. Reduced felt recoil is a regular mention, which helps during long competition days.

Build quality and ergonomics draw favorable comments. The matte blued finish holds up to handling, and the adjustable stock is appreciated for accommodating different shooters. The competition-focused features (loading port, oversized charging handle, pinch-free elevator) are noticed and appreciated by shooters who have used other platforms.

Weight is the most common criticism. At 7.75 lbs it is on the heavier end of competition shotguns, which some shooters feel during extended matches or carry. Price is occasionally flagged as high, though most owners accept it as appropriate for a purpose-built competition gun. Overall the 940 Pro JM has a strong reputation in its category.