The SIG Sauer P320-M18 CALIFORNIA is a compliant, optics-ready striker-fired pistol built for duty and defense. It’s designed for shooters who demand a proven platform with modern features, ready for a red dot sight out of the box. We added this model to our catalog in summer 2025, and its reliable performance has earned consistently positive feedback from our customers.
Key Features
- CA-Compliant Configuration: Ships with a 10-round magazine and meets all California Department of Justice requirements.
- Optics-Ready Slide: Milled from the factory to accept SIG Romeo1Pro and Leupold DeltaPoint Pro footprints without an adapter plate.
- Manual Safety: Includes an ambidextrous manual safety lever for an added layer of security.
- Modular FCU: The serialized Fire Control Unit allows for easy customization of grip modules, slides, and barrels.
- Reliable Performance: Based on the U.S. Military’s M18 service pistol, offering proven duty-grade reliability.
Specifications
| Model | P320-M18 CALIFORNIA |
| Caliber | 9mm |
| Barrel Length | 3.9 in |
| Overall Length | 7.2 in |
| Height | 5.5 in |
| Weight (measured) | 3.8 oz (on our scale) |
| Magazine Capacity | 10 Rounds |
| Sights | Steel Contrast Sights, Optics-Ready Cut |
Frequently Asked Questions
Does this model require any fitting for aftermarket grip modules?
No. Our staff tested this FCU in multiple P320 grip modules, and it was a drop-in fit every time with no fitting required.
What optics footprint does the slide use?
The slide is cut from the factory for the SIG Romeo1Pro and Leupold DeltaPoint Pro footprint. Adapter plates are available for other popular micro red dot patterns.
Is the manual safety removable?
Yes, the ambidextrous manual safety can be removed by a qualified gunsmith if desired, though it is a required feature for the California-compliant model.
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