The last handgun I carried in uniform was the SIG Sauer M17, the full-sized sibling to the M18 pistol. Introduced in 2017, the M17 replaced the U.S. Armed Forces’ standard issue Beretta M9 and M9A1. The M17 was a fantastic duty gun: accurate, lightweight for its size and reliable. I swapped its Coyote grip frame for black to match my uniform, giving it a slick two-tone look. That pistol served me well, and I still wish I had it.

The M18 was designed as a more compact version of the M17, ideal for plainclothes work or anyone needing a slightly smaller duty pistol. I’ve watched midshipmen at the U.S. Naval Academy compete with stock M18 pistols and do remarkably well against competitors using “full race” guns with red dots and other upgrades.

Now, the new M18X pistol builds on that legacy. The upgrades from the original M18 aren’t flashy, but they’re meaningful. These refinements make the M18X even more attractive for civilian and law enforcement carry.

What Is the SIG Sauer M18X?
The SIG Sauer M18X is an upgraded, compact duty pistol designed for military, law enforcement and civilian use. It features a Coyote-colored frame, a flat-faced X-Flat trigger, an extended magazine well and comes equipped with a factory-installed Romeo M17 red dot sight co-witnessed with Siglite tritium night sights. The M18X ships with three 21-round magazines, offering enhanced capacity while retaining the proven reliability of the M18 platform.

M18X Pistol First Impressions

SIG ships the M18X in a hard plastic, lockable case, but the first thing I noticed were the three 21-round magazines with Coyote color base plates. The M18X is ready to go with 64 rounds. If I were a young officer today, I’d feel extremely well-armed with this level of firepower.

Concealed carriers, however, have more to consider. The additional six rounds in a 15-round space extend the magazine past the bottom of the frame by 1 inch. This could cause printing under a cover garment. If concealability is the priority, a simple solution is to switch to a standard 15-round magazine for daily carry.

SIG X-Series Features

Both the M17X and M18X pistols come with an extended, funnel-shaped magazine well that enhances reload speed and gives the pistol a professional look. Both handguns are competition-capable out of the box.

The Coyote-finished grip frame is gently stippled on the frontstrap and backstrap as well as on the sides. It is raised just enough to enhance the shooter’s grip during inclement weather but not so much as to make the M18X uncomfortable to shoot or be abrasive against clothing.

The trigger guard is undercut to provide an optimal grip. A molded-in M1913 accessory rail sits forward for attaching a light, laser or both. A gently extended beavertail improves control and comfort, a noticeable difference from the standard M17 and M18 when viewed side by side.

The magazine release button is positioned just aft of the trigger on the left side and is very easy to access. The slide release levers are ambidextrous and easily accessed by either thumb. The takedown lever is on the left side of the frame.

There is no additional manual safety for either the M17X or M18X. Hopefully that option will become available down the road for those of us who prefer an extra layer of security.

The flat-faced X-Flat trigger replaces the curved version found on the standard models. My Wheeler trigger pull gauge measured it at 5 pounds, 13 ounces — ideal for duty or defensive use.

Optics and Sight System

Fans of red dots will appreciate that the M18X pistol ships with SIG’s Romeo M17 Red Dot Sight factory-installed. It is co-witnessed with the SIGLITE tritium iron sights. In low-level light, the SIGLITE sights will help guide you toward the red dot inside the Romeo M17 sight.

The Romeo M17 features four primary controls. On the left side are two brightness buttons: an upward-pointing arrow that also serves as the power button and the downward arrow reduces brightness. Windage and elevation adjustments are handled via screws placed conveniently for user access. The optic blends seamlessly into the Coyote slide finish.

SIG Sauer M18X Specifications

Caliber: 9mm Luger
Magazines: Three steel 2-round magazines included
Finish: Coyote PVD
Slide construction: Stainless steel
Trigger action: Striker-fired/X-flat trigger
Grip module: X-modular polymer
Fire control unit: Stainless steel
Barrel material: Carbon steel
Barrel length: 3.9 inches
Overall length: 7.2 inches
Overall width: 1.6 inches
Height: 6.3 inches
Weight: 30.8 ounces
Sights: Romeo M17 red-dot and SIGlite three-dot tritium sights
Accessory rail: M1913
Price (Guns.com): $1,429

Shooting the M18X

I had the opportunity to test the M18X when my former law enforcement agency needed assistance in firearms qualification. As a retired officer, I needed to run through pistol qualifications before I could sign off on the department’s rifle instructor. Though the M18X is larger than I would prefer to carry concealed on a day-to-day basis, I wanted to see how it would work for me during qualification.

I’ve always preferred red dot sights on rifles, shotguns, and PCCs—shoulder-fired platforms where the optic naturally aligns with your eye every time you mount the gun. The dot is right there, no hunting required. Pistol-mounted red dots are a different story. Since handguns are held farther from the eye, finding the dot can take practice. I’m not knocking them, though. Plenty of skilled shooters run them with incredible speed and accuracy.

That said, at 68, I’m just not willing to invest the time it takes to master a red dot on a defensive pistol. I knew going into the qualification it would be a challenge.

On the Firing Line

The State of Ohio Peace Officer Qualification Course consists of 25 shots fired from the duty handgun. These rounds are divided across six stages of fire, one requiring a head shot and others requiring reloads, with distances progressing from 4 feet to 50 feet. Firing is all from the standing position using one- or two-handed shooting stances. The most shots required at any one stage is eight. Time limits run from 5 to 15 seconds, depending onthe  stage.

Qualifications require a holster, and luckily, the Kydex Blade Tech I had on hand from carrying the M17 worked, though it was a bit tight with the light attached on the M18X.

SIG provided me with several boxes of 9mm V-Crown Elite Defense 124-grain JHP Ammunition with a muzzle velocity of 1,165 feet per second and 374 foot-pounds of energy. It is an ideal load to use for testing a combat pistol. Two magazines with 15 rounds each would provide plenty of ammo for all stages of the course.

I found the 18X reliable through 25 rounds across all stages. On Stage 4, I inadvertently locked the rotating hood on my holster, causing a delay that cost me three rounds outside the time limit. However, the M18X was an excellent performer on the course. There were no malfunctions with the SIG ammo or the department FMJ ammo the officers had brought along.

My biggest challenge was quickly acquiring the red dot after reloads — a clear reminder that red-dot pistol shooting requires consistent training. When I handed the M18X to another firearms instructor well-versed in red dot pistol shooting, he immediately demonstrated how quick and precise the setup could be when properly trained.

Why the SIG Sauer M18X Stands Out for Duty and Defense

The SIG Sauer M18X is a formidable tool for anyone seeking a reliable self-defense handgun, a capable duty pistol or a competition-ready platform. The combination of high-capacity magazines, ergonomic improvements and an out-of-the-box red dot sight makes it an exceptional choice.

The M18X pistol is currently available for $1,429 at Vance Outdoors in Columbus, Ohio. It’s a worthwhile investment for anyone serious about personal defense or professional duty use.

Sources:

Vance Outdoors: VanceOutdoors.com
SIG Sauer: SIGSauer.com
Streamlight: Streamlight.com
Blade Tech: Blade-Tech.com