SIG Sauer P320-M18 MS 9mm Carry, Coyote, Night Sights, Optic-Cut Slide, 3.9" Barrel, 21+1 Capacity
This P320-M18 MS is the commercial near-spec counterpart to the U.S. military's M18 from the Modular Handgun System program. It combines a 3.9" compact-length slide on a Carry-size grip with a coyote PVD slide, coyote polymer frame, steel 3-dot night sights, and an optic-cut slide with a removable rear sight plate. It also features the P320's removable serialized FCU architecture for modularity and includes an installed Brouwer M1811 grip module. Three factory steel magazines are included: two 17-round and one 21-round.
Introduced on December 3, 2019, the M18 pattern has been adopted across U.S. armed services, with the USMC standardizing on the M18 in 2020. This variant uses the P320 striker-fired action and an ambidextrous manual thumb safety. It ships with a SIG Sauer factory case, owner's manual, and an M18 patch, making it a well-equipped example of the M18 configuration for duty, range, or collection.
Condition
Overall Condition: Very good condition, showing only light, superficial signs of prior handling or use.
Bore Condition: Excellent - Clean, mirror finish, no signs of wear.
Bore Rifling: Excellent Rifling - Sharp lands and grooves.
Specific Condition Notes: There is minor handling wear. Function is excellent.
What’s Included
- SIG Sauer factory hard case
- SIG Sauer owner's manual
- M18 patch
- Brouwer M1811 grip module (installed)
- 2x 17-round factory steel magazines (marked "MADE IN ITALY")
- 1x 21-round factory steel magazine (marked "MADE IN ITALY")
The M18 configuration delivers a compact footprint with a 3.9" barrel and 21+1 capacity when paired with the included 21-round magazine. The slide is finished in coyote PVD and is machined with an optic cut, using a removable rear sight plate that retains the steel night sight when installed.
Controls align with the military pattern, including an ambidextrous manual thumb safety. Steel 3-dot night sights come standard, with a steel front and a steel rear mounted on the removable plate. An accessory rail on the frame allows for light or laser attachment as needed.
The P320 architecture centers on a removable serialized fire control unit (FCU), enabling modularity across grip modules and configurations. This pistol includes a Brouwer M1811 grip module installed, offering a distinct grip module choice right out of the box.
As the commercial near-spec counterpart to the U.S. military M18, this variant reflects the program lineage introduced in late 2019 and fielded broadly across U.S. services, with the Marine Corps standardizing on the M18 in 2020. This model also follows the M18A###### serial prefix convention used on this variant.