The Sig Sauer P320 M17X is a full-size striker-fired pistol chambered in 9mm Luger (9x19 Para) with a 21+1 round capacity. It has a 4.7-inch barrel, measures 8 inches overall, and weighs 29.6 oz (2.06 lbs). The finish is Coyote PVD. The frame is polymer with stainless steel components. Sights are Siglite Night Sights. 
 

Key Specifications 

• Brand: Sig Sauer 
• Model: P320 M17X 
• Action: Semi-Automatic (Striker Fire) 
• Caliber: 9mm Luger (9x19 Para) 
• Barrel Length: 4.7 inches 
• Overall Length: 8 inches 
• Capacity: 21+1 rounds 
• Weight: 2.06 lbs (29.6 oz) 
• Finish: Coyote PVD 
• Material: Polymer frame with stainless steel components 
• Sights: Siglite Night Sights 
   

Detailed Features 

 
The 21+1 capacity is the standout spec here — 21 rounds in a standard magazine is high for a full-size service pistol. Siglite night sights come standard for low-light use. The XSeries flat trigger gives a consistent break and short reset. The Coyote PVD finish is a corrosion-resistant alternative to standard black. 
 
The modular P320 design means the serialized fire control unit can be moved into different grip modules, which gives ongoing flexibility. At 29.6 oz it is comfortable to shoot for extended sessions.

The P320 M17X draws positive feedback overall. The modular design is frequently cited as a genuine advantage — owners appreciate being able to reconfigure the pistol without buying a new serialized unit. The 21+1 capacity is a specific selling point for buyers who want a high-round-count duty or home defense pistol.

Ergonomics get good marks. The grip fits comfortably and the Romeo X optic (where included) improves target acquisition for shooters transitioning to red dots.

Size is the main practical concern for some buyers. The full-size form factor makes it less practical for concealed carry, and a few users note it is on the larger side compared to competing duty pistols. Some report reliability issues during break-in or with specific ammunition types.

Overall the feedback reflects a well-regarded full-size pistol suited to duty, home defense, and competitive use.