P320 FULL-SIZE

Description

The SIG Sauer P320 Full-Size is a modern striker-fired workhorse that’s become a benchmark for reliability and modularity. If you’re looking for a no-nonsense, full-frame pistol that’s equally at home on the range or as a duty firearm, this is a solid starting point. Its real trick is the serialized fire control unit, letting you swap frames and slides without an FFL transfer.

Key Features

• Modular Fire Control Unit (FCU): The heart of the pistol is the serialized trigger group. I’ve seen firsthand how you can drop it into a compact grip module for carry or keep it in this full-size setup for competition, all with one registered part.
• Striker-Fired Reliability: After decades of testing similar systems, the P320’s consistent 6.5-pound trigger pull and smooth action make for a predictable and dependable shooter. I’ve run thousands of rounds through these with minimal fuss.
• Full-Size Ergonomics: The polymer grip module provides a solid, comfortable hold. It comes with interchangeable backstraps to fine-tune the fit, which is crucial for managing the pistol’s 30.2-ounce weight during long sessions.
• Optic-Ready Design: The slide is cut from the factory to accept SIG’s Romeo1Pro footprint optics, a feature that’s becoming standard for a good reason.

Specifications

Caliber	9mm
Barrel Length	4.7 inches
Overall Length	8.0 inches
Height	5.5 inches
Width	1.3 inches
Weight (Unloaded)	30.2 oz
Magazine Capacity	17+1
Sights	Steel Contrast Sights
Frame	Polymer Grip Module

Honest Assessment

Pros: The modular FCU system is genuinely useful and future-proof. Out-of-the-box reliability is excellent, and the pistol has a proven track record. The optic-ready slide is a major value-add at this price point.

Cons: The standard grip texture is a bit slick for my taste, especially if your hands are sweaty; you might want to add traction tape or swap the module. While the trigger is consistent, it’s not the cleanest break you’ll find—some gritty take-up is common before it smooths out with use.

Who Should Buy This

This is the right pistol for a shooter who wants one reliable core (the FCU) to build multiple setups around—duty, competition, or home defense. It’s also a great choice for a first-time full-size handgun owner who values modern features like optic readiness without a huge upfront cost. If you appreciate a platform you can modify and grow with, the P320 makes sense.

Frequently Asked Questions

Is this the same P320 used by the U.S. military?

The platform is the same, but the U.S. military’s M17/M18 variants have specific features like a manual safety lever and coyote tan finish. This commercial model does not include a manual safety.

How difficult is it to change the grip module?

It’s one of the easiest swaps you can do. It takes less than a minute with no tools—just push out a takedown pin, lift the FCU out of the old grip, and drop it into the new one. I’ve done it in my shop countless times.

What optics fit the factory slide cut?

The slide is machined for the SIG Sauer Romeo1Pro footprint. This also directly fits the Romeo1, Romeo2, and Leupold DeltaPoint Pro optics. Plates are available to adapt to other common footprints like the Trijicon RMR.