SIG Sauer P320 X-Five – Modularity at its best

During our company visit at SIG Sauer in the USA at the end of April 2018, we also had the opportunity to once again closely inspect the P320. What separates the SIG Sauer P320 from many competitors is its exceptional modularity and versatility.

To speak of modularity is one thing, to translate it into reality in a thoughtful way is another. And here SIG Sauer has done an excellent job.

SIG Sauer M17 service pistol of the American Armed Forces
The SIG Sauer P320 X-Five sporting pistol is based on the same technology as the new duty pistol used by the American armed forces.

SIG Sauer P320 modular handgun: features

SIG Sauer P320 X-Five modular match pistol lies on 9 mm Luger ammunition
The SIG Sauer P320 X-Five in 9 mm Luger is a modern polymer frame striker-fired pistol with a sporty look. Here, the firearm of the SIG Sauer Academy trainer with additional skateboard tape on the frame.

By means of the removable trigger of the P320, which being an essential firearm component carries the serial number, you can quickly and simply replace the commercially available frame. It is already on the market for 69 euros in three sizes: full-size (17 rounds, 9 mm Luger), compact (15 rounds, 9 mm Luger) and sub-compact (12 rounds, 9 mm Luger). 

With the appropriate conversion kit with barrel lengths of 120 mm, 100 mm and 91 mm, the pistols can then be configured into the ideal size for the shooting range, the beat or discrete, concealed carry for self-protection. 

Caliber conversion is also possible. While the .45 Auto stands alone and “only” its frame size and slide length can be changed, between the .40 S&W and 9 mm calibers there is complete interchangeability. The version in .357 SIG, the powerful cartridge that was launched in 1994 in cooperation with Federal and somewhat exotic in Europe, for the P320 series is unfortunately only available in North America.

The SIG Sauer P320 X-Five in detail

The model designation should awaken associations with the P226 X-Five stainless steel match pistol – both models have a 5” (127 mm) long bull barrel. The slide, made of stainless steel, is black nitro-carburized and on its upper side is equipped with three different sized ports, which slightly reduce the slide weight. Aside from the windows in the front of the muzzle area, the slide is also embellished with a milled slot, where we see the sign of the times: a mini red dot sight (MRDS) can be mounted there. 

Sport pistol SIG Sauer P320 X-Five with 9 mm Luger ammunition packaging
Athletic attributes: the P320 X-Five include a first-class grip with magazine well funnel; a clean trigger with a short reset; a very practicable, mechanical sight and the option of an MRDS.

However, as a full supplier the company more or less forces P320 X-Five buyers to purchase an in-house SIG Sauer Electro-Optics Romeo1 reflex sight, as the manufacturer offers no adapter plates for other MRDS makes. Yet the accessory market has already reacted and accordingly offers - for example, Springer Precision - the appropriate interfaces for Trijicon RMR, Vortex Venom (and thus also the Docter Sight I–III that uses the same mounting base), Vortex Razor or the Leupold Delta Point Pro. 

SIG Sauer P320 X-Five match pistol between packs of 9 mm Luger ammunition and 2 double-stack magazines
The double-stack magazine shows a high capacity of 21 rounds.

The cover plate for the milled slot, which stays on the slide when shooting without MRDS, houses the micrometer rear sight. This way you have an elegant unit that sits deep in the slide, offering in combination with the narrow 2.25 mm Dawson front sight a practically oriented, mechanical sight. 

The sportiest model of the 320 series features a full-size X-Grip frame. It differs from the standard versions because the recess on the bottom tip of the frame is missing, which facilitates a resolute grip on the magazine. For that reason, a detachable magazine well funnel made of aluminum facilitates the switching of the 21-round steel magazines. 

Hidden weight in the frame – For what purpose?

TheSIG Sauer P320 X-Five with Browning-Petter-SIG system and 5” bull barrel disassembled 
The disassembled P320 X-Five with Browning-Petter-SIG system and 5” bull barrel.

Additionally, the area at the junction of the frame front and the trigger guard has been more heavily hollowed out. The grip spur has also been extended. Thus the polymer X-5 rests more securely in your hand, ensuring less muzzle deviation when shooting. In comparison with the standard frame, what stands out is the lacking thumb recess around the magazine release. This way it was possible to implement the fine, non-slip checkering on the lateral surfaces up to the top. 

The technicians at SIG Sauer also  supplied this polymer sporting piece with an internal weight. It weighs nearly 48.5 grams and is positioned vertically in the rear area of the frame, where in many striker-fired pistols there is a hammer spring. Since it has been positioned behind the pistol’s center of gravity, it cannot be of much help with muzzle rise, however it may slightly reduce recoil. Additionally the spring guide rod is made of steel, which also provides additional weight. 

The exactly 126 mm long barrel features a lightly recessed muzzle and a diameter of 16 mm. Thus, in diameter it has about 2 mm more mass than the P320 standard barrel.

The slide release is on both sides, and the magazine release button can be moved to the other side, which should please lefties. In the middle, the trigger has a straight tongue and breaks at just under 2,000 grams requiring a 3.5 mm reset.

The sportiest model of the P320 series costs, with a spare magazine, 1,375 euros (RRP). 

The complete overview of the P320 series as well as a link to the retailer search can be found at the following manufacturer website.

The legendary SIG Sauer Academy is considered the largest commercial shooting school in the US. We had the unique opportunity to spend a few days on site.

Live Shooting of the SIG Sauer P365: as we noticed during our visit to the SIG Sauer Academy in shooting practice, the latest subcompact pistol from the manufacturer is extremely powerful.

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