SIG Sauer, capitalizing on the success of the P320 handgun, is now shipping three additional P320 variants. These three pistols, part of the X-Series, are unique in several different ways but are still P320s at heart. This means these pistols still share the same modularity that makes the P320 such a unique firearm in the marketplace, and conceivably allows the shooter to buy one P320 and convert that one pistol into a full-size, compact or subcompact handgun in 9 mm Luger, .357 SIG or .40 S&W by purchasing the appropriate conversion parts. Conversion parts are available now (or should be soon) as individual components or as complete exchange kits. 
The three pistols currently being sold in the X-Series are the X-Carry, the X-VTAC and the X-FIVE. The X-Carry has been thoroughly and expertly reviewed by Joe Kurtenbach. His three-part range report can be found at americanrifleman.org/gear.
Guns in the X-Series all ship with the X grip module, which is squarer and flatter along the edges than the standard grip module, giving these pistols a slightly boxy feel. The X grip’s beavertail has been extended and scalloped and the trigger guard is aggressively undercut. These changes allow the shooter to obtain a higher grip on the pistol, which can help reduce “muzzle flip.”
Another feature unique to the X-Series is a flat, rather than curved, trigger, coming to rest at 90 degrees. This is said to help keep the shooter from pushing the gun off target as the trigger is pressed to the rear. Also, it allows the shooter to place the trigger finger slightly lower on the trigger. The lower the finger can be on the trigger, the farther it is from the trigger’s hinge point. This can help increase leverage and reduce the trigger’s perceived weight.
Since the X-Carry model has already been reviewed, I will focus on the X-VTAC and X-FIVE. Up first is the X-VTAC. For those not familiar with VTAC, it is an acronym for Viking Tactics. Viking Tactics is a training endeavor operated by Kyle Lamb, a retired U.S. Special Operations soldier with more than 20 years of military experience. He is widely respected in the firearm training realm and is a published author, industry consultant and all-around nice guy. Having attended several training classes taught by Kyle over the years, I was eager to shoot his take on the “perfect” P320.
The P320 X-VTAC is a full-sized pistol chambered in 9 mm Luger. It ships in a plastic box that includes three 17-round magazines. The VTAC’s slide is PVD-coated a dull Flat Dark Earth and is topped with VTAC sights, which sit a little taller than conventional pistol sights, but that’s because they contain two different sets of dots. At the top of the sights are fiber optic dots that shine nicely in direct sunlight. Underneath the fiber optic inserts are tritium inserts for nighttime/reduced light use.
My initial reaction was that the sights are overly complex and offer a busy sight picture, but that wasn’t the case at all during live fire. My eye naturally focused on what needed to be seen and I was not distracted by the extra set of dots on the sights. One caveat about the sights: The VTAC is sighted in to provide a “combat sight picture” at 10 yards. This means that the pistol shoots low when using the top edges of the sights. Rather a “just above center mass” hold was needed to get the pistol to shoot point of aim during accuracy testing. 
Once I was used to this hold I had no issues with accuracy. Some shooters will no doubt dislike having to re-learn and may wish to opt for something else. No matter, as the P320 X-VTAC uses the same sight dovetails as the standard P320 series.
The X-VTAC will no doubt appeal to those who like the gun's unique look, want something a bit different or who are fans of Kyle Lamb and Viking Tactics.
Next up is the P320 X-FIVE. This pistol is SIG’s full-on competition pistol and is ready for USPSA, 3-Gun or just about any action pistol sport. The X-FIVE comes with four 21-round magazines that protrude below the bottom of the frame but the standard 17-round magazines can also be used if desired or required by applicable rules. To further enhance the pistol’s appeal to sport shooting, the X-FIVE is outfitted with a flared steel magwell for ease of reloading. The grip module contains a removable weight that helps increase mass and dampen recoil. The weighted insert can be removed for personal preference or to meet division weight rules.
The X-FIVE’s slide comes equipped with a fiber optic front sight and a target rear sight that is fully adjustable for windage and elevation. Additionally, the slide is machined to accept a slide-mounted red dot optic with the removal of the rear sight assembly.
One interesting possibility, tied directly to P320 modularity, is that the X-FIVE can easily be converted from 9 mm Luger to 40 S&W by installing a new top end and changing the mags. This means that this one pistol can be configured for USPSA Limited division with a simple field strip and reassembly. Mags can be downloaded to ten rounds for Limited Ten or extended base pads can be purchased from Springer Precision, Taran Tactical or Taylor Freelance to increase magazine capacity and make the X-FIVE 40 S&W competitive in Limited Division. One pistol to learn with the same trigger across multiple shooting disciplines. How cool is that?
During testing, I found both pistols to be quite accurate and, as expected, completely reliable. The X-FIVE proved accurate with all loads tested including a personal handload with a hard cast lead semi-wadcutter from Montana Bullet Works. Competition shooters often use reloads for matches and for practice so I thought it was appropriate to include at least one handload in the test. Please keep in mind that using remanufactured or handload ammunition will likely void your pistol’s warranty.
The P320, on its surface, doesn't appear to offer much that can't be had from most other designs. So it has a removable grip module. What’s the big deal? It turns out the removable plastic frame gives the 320 a great deal of flexibility. Think of it as the pistol version of the AR-15. The AR-15 is built around the serialized lower receiver. To this lower receiver can be added any number of uppers in any number of barrel lengths or caliber choices. This same lower can accept a differing number of stock and pistol grip options. In a similar fashion, the P320 can be put together and configured to meet nearly any want or need. The completely modular pistol, in my opinion, will be the standard by which future designs are judged. SIG has left the rest of the industry playing catch up!
Additional Reading:
SIG Gambles Big and Wins
NRA Gun Gear of the Week: SIG Sauer P320 X-Carry
SHOT Show 2018: SIG Sauer P320 X-Carry Pistol
