A Complete Look at the Famous Sig Sauer P320 Lineup

When we saw that we had nearly every major variation of the Sig Sauer P320 series in the Certified Used Vault, we knew we had to take on the monumental task of a complete review of the series. It’s a big task for sure, because Sig does a great job of listening to their customers and then tailoring solutions through the P320 lineup to their needs

In fact, wouldn’t you know it, from the time we recorded the video to the time it went to post, Sig went ahead and released yet another variant, the P320 Spectre Comp. Whether we have every single P320 or not, there are still a lot of pistols to get through here, but before we do, we need to talk about what makes this gun so special.

A MODERN MASTERPIECE IN MODULARITY

Fire control unit — The Fire Control Unit (FCU) is the main reason this lineup is so special. (Photo: Paul Peterson/Guns.com)

In 2014, Sig released its newest progression to the world – the Sig Sauer P320. The company went a step further and established a sort of unprecedented improvement to an already popular design, making it even more versatile and customizable to the user. Sig’s engineers achieved this by creating a removable chassis system, which contains their Fire Control Unit that sits inside the frame of the handgun as the serialized firearm component.

Unlike other modern pistols, this revolution basically means that you can essentially purchase one firearm and, without having to go through multiple background checks and paperwork, you can change the size of the grip frame or slide to accommodate whatever role the handgun is set to achieve.

Sig Sauer P320 pistols — You can dramatically change your handgun in under a few minutes with a quick swap of the FCU. (Photo: Samantha Mursan/Guns.com)

From sub-compact designs all the way up to full duty-size pistols, the chassis can move to whatever module the shooter needs – all while keeping it simple, easy, and extremely inexpensive. While there are other major brands out there, you could easily spend three times as much on them when trying to have a set of firearms that are well suited for different situations. The modularity of the Sig P320 also leads to consistent training, having one basic system to train and rely upon no matter what environment or situation is thrown at it.

Available in 9mm, .357 Sig, .40 S&W, and .45 ACP, the P320 is a versatile option for anyone from conceal carry to military or police services.

MAKING IT TO THE MILITARY

The P320 was first adopted by the Army as the M17. (Photo: Samantha Mursan/Guns.com)

No truly great thing goes unnoticed, and that is especially true for the Sig P320. With the design coming to fruition in the mid-2010s, it was realized at the perfect time to enter into U.S. Army's Modular Handgun System trials. Up against stiff competition and a rigorous series of tests, the Sig P320 emerged victorious, winning contracts with several military branches.

Sig Sauer M18 — The M18 was later adopted by the Navy and Marines. It keeps the same grip size as the M17 but shortens the overall length. (Photo: Samantha Mursan/Guns.com)

The full-size military handgun was adopted as the M17, and it featured a frame-mounted safety, an FDE color, and an optics-cut slide. The M17 was supplemented by the M18, a compact version of the handgun that featured a full-size frame and compact slide. Both of these handguns feature flush-fitting 17-round magazines and extended 21-round magazines.

Joining the ranks of the M1911 and the Beretta M9, the Sig M17 will serve for many decades to come.

RED-DOT READY AND FLAT TRIGGER WITH THE RXP

Sig Sauer P320 RXP — The RXP offers the ability to add a red dot as well as the X-Series frame and trigger. (Photo: Samantha Mursan/Guns.com)

Understanding the need for a diverse weapon system, the Sig P320’s variants continue to grow and evolve with modern trends and advancements. Carrying over from the M17 series, the past few years has seen the idea of pistol-mounted optics explode. Sig Sauer’s optic line, the Romeo series of red dots, features several models that can mount to optics-cut slides. The P320 RXP, or Romeo X-series Pistol, is an optics cut P320 that also features the X-series style of frame and trigger, which came to be in the Sig P365 series of firearms.

With a flat trigger, a custom grip stipple, and the ability to mount a red dot to acquire targets more rapidly, this handgun in its full or compact size delivers rounds downrange with speed and accuracy.

HIGH-CLASS COLLAB WITH WILSON COMBAT

The Wilson Combat P320 is a collaboration that adds some really cool customizations. (Photo: Samantha Mursan/Guns.com)

Firearm collaborations are always one of the signs that a handgun has reached a certain plane of achievement. Wilson Combat is a premier manufacturer of high-end guns and firearms components that are widely regarded as exceptional throughout the industry. In combination with Sig, the Wilson Combat P320 is a custom full-sized handgun that has features like fiber-optic sights, a beveled mag well, and custom stippling. The handgun is as unique as it is beautiful.

LIGHTEN IT UP WITH ALLOY AND CUSTOMIZE WITH SPECTRE

Sig P320 AGX — The AGX series gives a throwback in look and feel to the Sig P220 lineage. (Photo: Samantha Mursan/Guns.com)

The P320 AXG - Alloy X-series Grip - is a P320 that really holds a close feel to the lineage of Sig P220 series. With a metal grip module, there is some added weight to this handgun, giving it a feel of power and durability. The weight of the frame helps the user maintain a solid purchase and control, while also bringing down muzzle flip. The AXG features an optics-cut slide, a beveled magazine well, the X-series grip style with a straight trigger, and lightening cuts on the slide to balance the weight of the frame. This handgun is a solid contender, ready to deliver rounds downrange accurately.

Sig P320 XCarry Spectre — The XCarry Spectre from Sig Custom Works offers a distressed look and a unique "X" cut in the slide. (Photo: Samantha Mursan/Guns.com)

Sig Sauer’s Custom Works shop also works closely on this line of P320’s, driving the point home that they are here to make this handgun a personal experience. The Sig P320 XCompact Spectre is a light, polymer-framed X-series handgun that is also optics cut and features a custom distressed finish. Lightweight and durable, this makes for a great choice for anyone looking for a dependable carry gun.

COMPETE WITH THE P320 MAX OR XFIVE LEGION

The next realm that the P320 is made to conquer is the world of competition shooting. The Sig P320 Max is a full-size pistol that features the TXG - Tungsten X-Series Grip - module, which has heavy tungsten inserts in the frame to create that counterweight – like in the AXG – which aids in keeping muzzle flip in check. This handgun features a match-grade barrel, a 1911-style recoil spring, a stainless-steel guide rod, a flat skeletonized trigger, custom serrations on the slide, a Romeo3Max red dot, and a beveled magazine well. With no iron sights and the Romeo red dot, this handgun is perfectly set up to run in a Carry Optics division competition.

Sig Sauer XFIVE Legion — The X5 Legion is another competition-ready pistol that also offers iron sights. (Photo: Samantha Mursan/Guns.com)

Maybe competition is not what you are looking for, yet the Max shows a lot of features that you do not want to miss out on. Worry not, the Sig P320 X-Five Legion shares many similarities to the Max, but it also includes aspects like lightening cuts and iron sights. With the TXG module and a 21-round capacity, the Sig P320 Legion, much like its predecessors, is designed to serve as a duty sidearm while offering a luxury experience to the shooter.

COMMEMORATIVE SERIES

Commemorative editions of firearms are typically found in models that have a long-established history, often seen with Colt Single Action Armys or Winchester Model 94s or 1911s. The P320 is still under 10 years in the market, and yet there are already commemorative versions available, confirming its solidification as one of the great firearms designs of our generation.

Commemorative Sig p320 — Sig already has several commemorative models available, such as this NWTF model. (Photo: Samantha Mursan/Guns.com)

This Sig P320 commemorates the National Wild Turkey Foundation and is adorned with artistic depictions of wildlife turkey. While that may not be everyone’s cup of tea, it does go to show the status that this incredible handgun has already achieved.

CONCLUSION

As you can see, Sig has only bolstered their reputation with the Sig P320, and they have encased themselves in history with this design. In a world of ever-evolving firearms, Sig always brings their A-game. Whatever the task is that lay ahead, damn the torpedoes, the P320 is ready for the fight.