Test: SIG SAUER X-Series 4 Models + Interchangeable System

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SIG SAUER  presented the new X-Series at the main domestic and foreign trae shows last year. Initially, the X-Five und X-Six, revamps of the P 226, were known in-house under the auspicious working title "Redesign". And to rework the successful semiautomatic pistol series, SIG SAUER drafted in a large number of internationally experienced marksmen to work alongside its own 'in-house tuner' Mastershop. 

Faced with intense competition, the underlying idea was to create a modular version at a better price. The reason behind the modular principle was to allow beginners, brand switchers and those moving between a variety of sporting disciplines to tailor their pistol to the specific requirements of their sport or the depth of their wallets, effectively creating a gun 'to grow into' and enabling upgrades for the best-price X-Press model, starter price €1,599, to include all the features the X-Line premium model Supermatch provides as factory fits. 

The portfolio comes with the Match and Classic series besides the Supermatch. The new X-Short version is also new, available in all lines and offering a snubbed 4.4-inch (11.78 cm) barrel. Converting between 9 mm Para and .40 S&W is no problem either, as SIG SAUER offers all X-Series models in these two calibers. A small-bore conversion kit X-Five .22 is set for release soon. Specialists can already place orders with the factory for a series of preconfigured packages, tailored to offer all the feature details and accessories needed in specific shooting disciplines, among them the X-Five Open for the matching IPSC class and the X-Six PPC and X-Six PPC Open for PPC 1,500 shooters. 

What's new?

The most striking difference compared with the 'old' X-Series, launched some ten years ago with the former X-Five, is seen in the beveled slide around the muzzle and the recoil-spring channel. Viewed from the front, the pistol's former rectangle, rounded at the top and with a slender 'U' located below, is replaced with a downward-pointing trapezoid.

The new slide design does more than merely lend the pistol a slimmer and trimmer look, it also reduces the weight of the slide and the mass set in motion when a shot is fired, impacting positively on the pistol's muzzle-rise behavior. 

Another immediately noticeable feature is that all of the X-Series models now boast a Picatinny-rail on the dust cover. Located at the rear two of a four-slot rail, in line with MilStd 1913, there is also a rounded recess for the in-house X-Mount, used to attach a variety of optical sights or the variable extra weight called X-Weight., which shifts the pistol's center of gravity pistol forward.

Another modification, previously reserved for the sport models but now on general release with the new X-Series, is the rear sight mount at the back of the slide, which the manufacturer has given the portending title of "multi-functional interface". Requiring practically no effort, this adapter plate facilitates a quick switch from fixed sights to a fully adjustable micrometer rear sight. It is equally possible to mount a module without a rear sight to integrate a slide racker for rapid reloading, provided an optical sight is fitted. 

You have to look closer to discover the other modifications: But at second glance, or maybe second clasp, you will notice that the surface of the hand-rest has been raised once more and that the checkered groove for the finger of the supporting hand at the front of the trigger-guard is deeper than before. Compared with the old X-Series, the raised hand-rest surface once again lowers the barrel's bore axis, permitting improved control of the pistol when shooting.

Previously you had to dismantle the grip plates to fit a jet funnel; Now the plates on the new X-Series come with a matching recess, while the frame accommodates a receiver at the end of the magazine well.

Testing the SIG SAUER X-Series versions

Besides the X-Short Conversion Kit, SIG SAUER provided an X-Five AL SO SAO, an X-Five SO SAO, an X-Five Allround and an X-Six Match for the test. All 9 mm caliber Para pistols came with a solid plastic case, one spare magazine, a user manual and a test target. 

SIG SAUER X-Series First Impressions

The first closer inspection of the models before us revealed: all of the pistols display first-class workmanship quality. The surface finish on the black and the stainless steel versions was flawless.

The transitions from the grip plates on all the test pistols -- whether plastic or laminated wood -- to the immediately adjacent operating elements fit perfectly. This applies equally to the magazine jet funnel (if fitted). The rear sights fitted just as snug into their dovetail guides. And the interchangeable rear sight adapters produced a precise fit in the interfaces we mentioned before.

A look at the inner workings of the test guns: Here also we find the typical excellence of SIG SAUER standards with only minimal tool marks and a completely smooth surface coating.

Duty pistol - the SO model in the SIG SAUER X-Series 

SIG SAUER uses the abbreviation SO for Special Operations to mark the models with which it is targeting the law enforcement market. The X-Series has two five-inch X-Five spinoffs in this category: The AL SO SAO and the SO SAO. But the version for €1,999 with aluminum frame is some 250 grams lighter than its all-steel sibling for €200 more. And that's it when it comes to differences between the two SO models. They both have the same inner workings, including the identical, non-adjustable SAO trigger (single action only trigger) and both come with nonslip black plastic grip plates. But thanks to an enlarged floor plate the magazine takes 19 9 mm Para rounds – two more than the standard magazine.

The slide catch, magazine catch and takedown lever are found only on the left side of the pistol, but there is a safety lever on both sides. To acquire targets, the pistols come with a laterally drifting, 3.5 mm wide post sight with a white contrast point seated in a dovetail and a rigid 3.8 mm cut in the rectangular rear sight, featuring a vertical white line beneath the cutout. 

Multitalented: SIG SAUER X-Five

The X-Five Allround surely provides for the greatest diversity of use. The operating elements of the stainless steel pistol are arranged along the left side, only: Breakdown lever, slide catch and magazine catch. Instead of a safety lever, the Allround has a button to decock the hammer safely. All of the operating elements are readily accessible. Then it has a SA/DA trigger that releases pre-cocked at around 1,600 g and in double action operation at a hefty 5,150 g, both without undue creep. 

SIG SAUER equips the pistols with black-grey laminated wood grip plates with checkered engraving in the form of the X-Series logo. The frame itself houses a factory-fit standard magazine with 17 round capacity. And on the slide we find sights consisting of a 3.2 mm post sight and a fully adjustable micrometer rear sight with a 3.8 mm wide cutout.

Fit for competition: X-Six by SIG SAUER

With its 'massive' sight length verified at 205 mm (if permitted), the SIG SAUER X-Six is best used wherever you need to deliver your shots smack bang into the center of the target. And the Allround sight-combination we described above and consisting of 3.2 mm post sight and micrometer rear sight certainly comes in handy. But the longer sight length means that the rear sight of the X-Six only sports a 2.7 mm wide rectangular cutout. The halo located between rear and front sight is narrower than on the Allround and also the SO versions, bringing added accuracy, but not necessarily speed, to target acquisition. 

In contrast, the aluminum Jet Funnel attached below on the frame allows for a rapid change of the 19-round magazine. The grip plates are like those on the Allround, and the operating elements resemble those of the SO models (with the exception of the magazine release button, which is elongated by about five millimeters). The Match comes with a SAO-match trigger, including a fully adjustable trigger blade position, a skeletonized trigger and a similarly skeletonized hammer. 

At the shooting range with the SIG SAUER X-Series

The shooting range confirmed the positive first impression the new pistols left. First of all the candidates were put through their paces in a function test. To do this the testers discharged several magazines containing both identical and mixed rounds in rapid succession through the barrel. Then came the precision test. Regrettably, time constraints placed on testing meant it was not possible to reconfigure the clamp jaws on the Ransom Rest shooting machine, which had been set for X-Series pistols, to accommodate models with levers. So the testers decided to test the X-Six Match and only one of the two SO-pistols in a seated position on the sandbag rest. But the X-Five Allround and then the X-Short-conversion kit frames were tested on the Ransom Rest.

This serves to qualify the final result, in which the X-Five delivered a 29 mm top group, five millimeters tighter than the X-Six Match. If it had also been a machine, we can only assume that the Match would have bettered this grouping – but that would only lead into the realm of reading tealeaves. What is pleasing: all of the pistols performed flawlessly. Neither feeding nor ejection jams occurred during the entire test.

Technical Data of the SIG SAUER X-Series in 9 mm Para 

Shooting test SIG SAUER X-Series in 9 mm Para

Summary of the tests of the SIG SAUER X-Series

SIG SAUER's new X-Series represents a well-designed pistol series with the customary good finishing and quality. Most of the models are located in the upper price bracket. Nevertheless, the dedicated accessories and conversion kits available for the new series mean that its modular design is suitable for modification or upgrade for use across a variety of disciplines. Given the restrictions on weapon permit entries applicable in Germany, this is surely not the worst idea for handguns. And when it comes to reliability and precision, you can't go wrong purchasing a model from the X-series.