SIG Sauer P320-XTen 10mm Auto Striker-Fired Pistol

The SIG Sauer new P320-XTen handgun, with its superb ergonomics, great durability and target-gun accuracy, might be the best 10mm out there. Brad Fitzpatrick gives us a full review.

June 29, 2023 By Brad Fitzpatrick

SIG Sauer has been on a hot streak lately. In addition to winning U.S. military contracts for its striker-fired pistol (M17/M18) and rifles (XM5 and XM250), the company’s P365 pistol has also been one of the hottest-selling guns for the last few years. Now SIG is entering another hot market, the 10mm striker-fired semiauto segment, and has plans to dominate that space with the launch of its P320-XTen semiauto pistol.

As the name implies, the SIG P320-XTen is derived, at least generally, from the company’s popular P320 9mm. Both are members of SIG’s XSeries line of striker-fired pistols, and the XTen shares the same beefed-up polymer grip module you’ll find on .45 ACP models.

The new grip module offers plenty of space and a comfortable modern microtexturing that wraps around the front, rear and sides. Unlike more outdated grip texture designs the SIG’s microtexturing isn’t overly aggressive.

SIG Sauer P320-XTen 10mm Auto Striker-Fired Pistol Controls — The SIG’s control layout features an ambidextrous slide stop and a reversible mag release. Ample space between the controls eases operation.

The grip angle keeps the hand high in relation to the bore axis, and an oversize beavertail prevents slide bite. The XSeries guns also feature a high undercut on the trigger guard for even more control when firing powerful loads.

The larger XSeries grip module allows it to hold 15-round double-stack metal magazines. The magazines themselves are high quality with appropriate weight springs. There’s a subtle mag well flare that makes it easier to reload the pistol in times of stress. The XSeries frame also offers an oversize trigger guard that allows you to shoot this gun even when wearing heavy gloves, and there’s a five-slot accessory rail on the dust cover for mounting lights and lasers.

Another feature from previous XSeries guns that’s made its way to the new 10mm version is the XSeries flat-face trigger. Flat-face triggers have become popular because they position the shooter’s finger lower than the traditional curved trigger. This allows for a smoother, more consistent trigger break and, in turn, better accuracy. The trigger is much lighter, smoother and more consistent than the more mushy triggers in competing striker-fired guns, and break weight is undisputedly better—just 4.5 pounds on average for 10 pulls. Reset is also very short.

Clean triggers with short resets are great for making fast shots with race guns, but this is a 10mm, a certified bear-stopper and hunting round. Can it still be fired quickly and accurately? Yes.

Since the time that the FBI dumped the 10mm in favor of the milder .40 S&W, much has been made about the 10mm’s supposedly ferocious recoil. It’s true that 10mms can be brutal to shoot if they’re poorly made or too light, but the XTen is neither of those.

SIG Sauer P320-XTen 10mm Auto Striker-Fired Pistol Trigger — The XSeries trigger has a straight profile. Take-up is smooth and light, and with a 4.5-pound break. Fitzpatrick thinks it’s one of the best striker-fired triggers on the market.

At 33 ounces with a distinctly nose-heavy feel thanks to its beefy slide and five-inch barrel, the SIG is one of the few 10mms you can use to drill center-mass shots quickly. Combine this balance-forward design with a substantial and well thought-out grip design and what is likely the best trigger of any striker-fired 10mm, and you’ll be able to shoot this gun in a hurry without spraying bullets all over the target.

Part of what makes this gun so fast is the standard sights. The XTen comes with dovetailed front and rear X-Ray 3 tritium night sights. The rear sight has twin dots that appear in low light (during full sun they are appear white) and a serrated surface to cut glare. The front sight features a chemical resistant fluorescent green dot that’s highly visible even in dim light and focuses attention on the front sight. A steel housing protects the tritium lamps and prevents chemical damage.

Like many modern pistols, the XTen comes with a slide that is pre-cut for optics. Not surprisingly, it accepts the company’s Romeo 2 reflex sight, and purchasing the sight and pistol together demystifies the mounting process because the sight is designed to fit the gun—including the screws. A Trijicon RMR sight can also be attached to the pistol using a plate.

SIG Sauer P320-XTen 10mm Auto Striker-Fired Pistol Barrel — With the five-inch barrel the XTen felt nose-heavy to Fitzpatrick, and he found it enhanced shootability.

The XTen’s stainless steel slide has Sig’s Nitron Ionbond, a non-glare matte black finish that is extremely durable. As with other P320 pistols, the XTen’s slide features angular corner cuts that minimize weight and simplify holstering. Slide serrations are found on the front and rear. Within the slide you’ll find a five-inch carbon steel barrel with a matte black finish. The fire-control unit is made from stainless steel.

The minimalist control layout is simple and functional. There’s an ambidextrous serrated slide stop that extends just far enough from the frame to be functional but doesn’t jut out far enough to hang up while drawing the gun. Unlike some striker-fired pistols the SIG’s slide stop is actually large enough that it can be effectively operated with the thumb.

A triangular serrated magazine release is tucked into a recessed portion of the frame just behind the trigger, and it is reversible. Takedown is simple thanks to a rotating takedown lever located on the left side of the frame.

With its five-inch barrel the XTen measures 8.5 inches long and weighs in at 33 ounces unloaded. Height is 5.6 inches, and width is 1.3 inches. That’s not much larger than the gun’s full-size 9mm stablemate, which measures eight inches long with a 4.7 inch barrel and weighs 29.5 ounces, but the XTen feels substantially bigger. Still, if you were inclined to carry a 10mm full-size pistol with a 15-round magazine you could conceivably do so.

I mounted the aforementioned Romeo 2 reflex sight on the XTen for testing, and it was great to have a sight designed to fit a pistol as perfectly as this pairing did. The sight held up well during hundreds of rounds with potent 10mm ammo, too.

I also shot the pistol with the iron sights. Once upon a time a striker-fired semiauto could get away with offering cheap plastic sights that weren’t very functional, especially if the pistol had a slide cut for optics. Those days are gone, especially when a pistol’s price tag is around $800.

SIG Sauer P320-XTen 10mm Auto Striker-Fired Pistol Accuracy Results

I like the sight layout, which features dual rear tritium vials and bright tritium/fiber optic front sight. During daylight hours the rear lamps are dim, but in low light they offer a frame of reference when aligning the sights. They’re also durable. The XTen’s 6.8-inch sight radius aids in accuracy.

The 10mm can indeed be a handful. Reduce a 10mm pistol’s proportions substantially or add a poorly engineered grip and these guns can become unpleasant. But the SIG P320-XTen is a good example—perhaps the best—of how to proportion a 10mm semiauto so it’s comfortable to shoot. As I mentioned, its nose-heavy feel when compared to a 9mm contributes to this, but the gun isn’t so heavy it’s unpleasant to carry.

Today’s striker-fired semiautos are undergoing a trigger revolution similar to the one that reshaped centerfire rifle design a couple decades ago. It’s more than just trigger shape, although the XSeries trigger’s straight profile is in keeping with the current trend.

The XTen’s trigger not only breaks at 4.5 pounds, it does so without the mushiness and grit that accompanies other striker-fired guns, even in this price range. The flat-front design and slightly upturned trigger tip makes for a lower finger position on the trigger and a more precise pull. I think this is clearly one of the top triggers in the 10mm market.

Now to the best part. The SIG XTen’s design and components make it extraordinarily accurate. From 25 yards in a Caldwell Pistolero rest and using the red dot, the gun managed to shoot five-shot groups with three different loads that hovered between 1.1 and 1.3 inches. One of the loads produced three shots that were touching, and on a couple others the group size would have measured close to a half-inch for four rounds.

Two of the loads that produced groups in the 1.25-inch-range were defensive ammo—Winchester Defender and SIG’s V-Crown—but the last was Federal’s 200-grain Fusion load, a bonded bullet designed for big game hunting.

In Ohio where I live, whitetail hunters can use handguns with barrels of at least five inches in length and chambered to straight-wall cartridges .357 or larger. According to those regulations the XTen is a legal hunting handgun, and based on the accuracy results I encountered it would do a fine job—and it would for wild hogs as well.

SIG Sauer P320-XTen 10mm Auto Striker-Fired Pistol Magazine — The XTen holds 15 rounds of 10mm ammo, which is handy for a bear gun, and with the right loads, it’s an excellent personal defense gun as well.

The XTen is perfect for defense against angry bears of all sizes. On my last two trips to Alaska, 10mm bear defense pistols outnumbered all other chamberings, so the 10mm seems to have become the go-to grizzly defense pistol.

The XTen is smooth-shooting and offers substantial capacity, but it is also light enough that it could be worn comfortably in a chest holster or even a hip holster. The Great North is notoriously hard on gun finishes, but the durable Nitron finish should stand up well to conditions.

Load with lighter self-defense 10mm ammo that more closely aligns with .40 S&W numbers, and the XTen turns into a mild-mannered self-defense pistol that is accurate and surprisingly easy to shoot. It’s not as fast through drills as a similar-weight 9mm, but it’s easier to keep on target than most competing 10s.

I ran it on Mozambique drills with various loads and found that it performed well. The only reliability issue was that the slide failed to lock back twice after the mag ran dry, but otherwise the gun ran splendidly.

I love the control layout, but I wish the slide stop was a bit larger. Add a little real estate there and it would be easy to bring the gun into battery without having to overhand the slide and optic to chamber a round, which can be rather awkward.

The magazines did drop free every time when the release was pressed, and even after bouncing around on gravel they worked well with minimal signs of abuse and no operational issues.

Retail price for the XTen runs around $799, which is more than the Springfield XD-M Elite and Smith & Wesson M&P 10mm 2.0 Full Size ($653 and $669, respectively) but less than the FN 510 Tactical ($1,139).

All of these pistols are optics-ready, and while the SIG matches the capacity of the Smith & Wesson, the Springfield holds 16 rounds and the FN up to 22 rounds of ammo. The SIG is the only pistol of the four that is available with a five-inch barrel.

The 10mm was almost dead once, but now it seems 10mms are popping out of every corner of the pistol market. The XTen is no longer the newest 10mm on the block, but it certainly is one of the best. As the market grows more crowded, this gun has the potential to come out on top.