The Game Changer: An Evolutionary Look at the Sig Sauer P365

Sig Sauer P365

The Sig Sauer P365 changed the concealed carry game. But how? (Photo: Josh Wayner/

The market for concealed carry pistols has been full for some time. Though not necessarily a problem, it seemed that the industry had begun to stagnate in developing truly different or new products. What essentially became standard was one of two options, a dedicated single-stack pistol or a cut-down version of a full-size gun — compromise was the established standard. Then Sig Sauer came along and shook that up.


How Did We Get Here? The Genesis of the P365


The Smith & Wesson Shield, and single-stacks like it, have been a favorite among concealed carriers. (Photo: Jacki Billings/

People have always carried compact guns in one form or another, but these small guns tended to be finicky and under-powered with lackluster accuracy. Small guns often struggle with effectiveness because of shorter barrels and a reduced sight radius. Additionally, smaller cartridges — like .380 ACP, .38 Special, and 9mm — grappled with power and expansion as the limited energy generated out of short barrels made them an undesirable liability for many concealed carriers.

It didn’t help that when the 9mm round was adopted for U.S. military service in the 1980s, it received harsh criticism. As wars and conflicts raged in Iraq, Afghanistan, and elsewhere worldwide, the 9mm round earned a perceived reputation as inadequate. NATO’s preference for full metal jacket rounds over hollow points put 9mm in a disadvantaged spot. The 9mm FMJ is not particularly heavy nor fast, and many Special Forces opted to go back to the larger .45 ACP round after 9mm failed to incapacitate enemies in combat. The fighting performance of 9mm seemed lackluster, and for that reason, many gun owners stuck with .45 ACP.

However, improvements in ammunition paved the way for an explosion in the popularity of dedicated concealed carry handguns in other chamberings. In the last decade or so, the hollow point truly reached its peak. Hornady, a major player in the ammo arena, created the advanced FTX bullet technology. This type of bullet features a polymer filler in the tip that aids in preventing clogging, which can prevent the projectile from expanding. This ammunition technology found its way into many common calibers such as .380 ACP, .38 Special, and 9mm.

Critical Defense

Hornady’s FTX technology revolutionized the way 9mm was viewed. (Photo: Hornady)

After the significant advancements in the mid-2000s, 9mm became a hot choice for carriers. The .45 ACP is still, of course, eminently effective, but 9mm now makes up that ground while offering lower recoil and greater capacity.

The mastery of the expanding bullet in the last 10 years opened up a whole new market. For the first time, ammo and guns could be compact and reliable while maintaining decent capacity. The popularity of single-stack carry guns exploded at this time, with companies like Ruger, Smith & Wesson, and Glock delivering affordable and reliable self-defense pistols in this budding category.


Guns like the Smith & Wesson Shield dominated the concealed carry arena. (Photo: Jacki Billings/

The Glock G43 and G42, Smith & Wesson Shield and Bodyguard 380, and the Ruger LCP and LCR dominated the carry field uninterrupted for a decade with slim profiles. The G43 itself went on to become something of a standard for all single-stack carry pistols. It was reliable and relatively accurate, but most people ended up adding a +1 extension to make up for the reduced capacity. That introduced another problem — the grip — which proved excessively narrow. The gun was nevertheless quite popular and developed a good following and aftermarket support.

The point at which the Sig Sauer P365 arrived is critical to the success it enjoyed. The market for carry pistols was stale with no company offering significant advantages over the other. Most carry guns were miniaturized versions of existing full-size designs — nothing truly groundbreaking or all that creative.

That is, until the P365.

The P365 Shakes Things Up

Sig Sauer P365

(Photo: Josh Wayner/

The P365 was smaller than the G43 but carried 10 rounds instead of six — representing a massive shift in the industry. Sig Sauer, a company that had most notably replaced Beretta as the Army’s preferred sidearm, had pulled the rug out from under the carry industry.

The P365 didn’t start as something extraordinary, though. “The first victim of the P365 was complacency,” Sig Sauer’s Phil Strader explained to “The capacity created an entirely new class of pistol. When we began looking at the concept of a next-generation carry pistol, it actually started as a single-stack back in 2015. The overall conceptual design of the P365 didn’t change much, and there was great struggle to bring it to fruition. Turning the trigger return spring sideways solved a number of design issues. The magazine design is what enabled this to become a game-changer.”

The P365 became something of a market disruptor. The gun did not exactly reinvent the wheel, but its revolutionary characteristics meant competitors had to keep up.

Delta Point Pro

The Sig P320 is the older, larger sibling of the P365. (Photo: Taylor Thorne/

Like its big brother the P320, the P365 introduces a modular design with a serialized internal chassis that houses the fire controls. As a result, the grip is simply a polymer shell that can be replaced in seconds. Traditionally, polymer-framed guns feature serial numbers on the frame itself, meaning if you mucked it up in a stipple job, you were basically out a whole gun. Not the case with the P365. The grip module is a cost-effective part, so you can easily afford to mess one up customizing it. You can also easily replace it should it crack or become damaged in use.

The modular design also introduces a drop-in ability meaning that, just like its larger sibling, the P365 can change grip sizes and magazine sizes rapidly. Not to mention, lights and lasers are easy to toss on, and users can adapt to technological changes as aftermarket accessories develop in earnest. Considering there is no custom work involved, and everything is serviceable at the user level, the P365 product line makes tremendous sense to those looking to maximize their gun.

The larger capacity magazines are adaptable to both the standard 10-round grip module and the slightly bigger P365 XL — which itself is a fantastic gun that blends the best features of the P365 with the ergonomic qualities of the Sig X5 line. This gun has a 4-inch barrel and a 12-round standard magazine. Users can adapt the mags to work with either grip size using interchangeable base pads. Not only is the magazine situation ideal, but the slide assemblies are also drop-in. The XL slide length will fit the standard 10-round grip module if the shooter wishes to go with that style of carry gun.

Sig Sauer P365XL

The Sig Sauer P365 XL gave more room for larger hands. (Photo: Josh Wayner/

A bonus is that the XL grip module fits the standard-size P365 slide. While it may not seem like much, shooters with large hands need that extra grip length (and many hate having to deal with the textured bases that are on many longer magazines.) The XL module fits the hand like a glove, providing excellent control over the gun.


Another slick addition to the P365 line was the P365 SAS, an incredible variant of the design that is fully modular and able to integrate with other P365 parts. Sig offers a standalone SAS slide upgrade complete with the fiber-optic gutter sight with tritium inserts. There are no traditional sights on this model, but it doesn’t need them. The slide can be fitted to any P365 model and delivers an advantage to those looking for a snag-free carry gun. What you have with the P365 is a family of products that all work hand-in-hand with one another.

Related: Check out our review of the P365 SAS

How did the P365 shape the modern carry industry? Stay tuned as we dive into the P365’s impact next week in part two of this look into this innovative pistol family.

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