Civilian shooters often only get their hands on advanced firearms technology long after it’s been introduced to the military. In the case of the Sig Sauer P320 series, this new truly modular handgun has been released into the general market at least a year before it begins to compete in the Department of Defense’s competition for a new sidearm for the military. That may mean that this is actually one of the world’s largest field trials, but if that’s what it takes to be able to own a P320, it’s worth it.
For the sake of this Sig Sauer P320 compact gun review, we’ll focus on the 9mm pistol, although the series is actually comprised of 9 different handguns (soon to be 12) in one. At the heart of the system is the stainless steel frame, the part of the pistol with the chamber, trigger assembly, rails and the serial number that requires all the BATF paperwork. Add a 9mm barrel, slide (with the appropriate spring), grip module and 15-round magazines and there you go: a Sig Sauer P320c 9mm double-action striker pistol in carry (medium length) size.
The dimensions of the P320 compact are 7.2″ overall length, with a height of 5.3″ and a 3.9″ barrel. The weight, with magazine but not ammunition, is an even 26 ounces, well within what most people would find comfortable for all-day carry. The magazines are 15 round capacity. For sights, there are two options: the SIGLITE® night sights or contrast sights. The slide is stainless steel, with a Nitron finish; the grip assembly is polymer, with a Picatinny rail (not the Sig Sauer proprietary rail) mounted in front of the trigger guard. Buyers can choose from a standard barrel or one that is threaded for a sound suppressor; a tabbed trigger safety is not standard (more on the safety system), but it can be added.
If, you decide later, that 9mm isn’t the caliber you need for a particular purpose, you can switch to .357 SIG or .40 S&W simply by ordering a conversion kit. Note that the P320 will be adding .45 ACP to the caliber choices, possibly because they may be competing for the DoD contract (there are rumors that the Pentagon, tired of hearing about the performance of the 9mm round, are considering switching back to the .45 — and the 1911 fans will dance in the streets, if that happens). Of course, since the conversion kit just includes the spring, barrel and magazines, you don’t have to go through an FFL purchase.
Or, you decide at some point that you’d really like to have a sub-compact Sig Sauer. No problem: Just buy the sub-compact grip assembly and slide. The same is true if you want to go to the full- size frame. Since the stainless steel frame is not an integral part of the grip assembly, you can keep your original frame and just change the size of the overall pistol. All without a Form 4473 in sight. Note that grip assemblies from the Sig Sauer P250 can be used with the P320 series.
This ability to change caliber and grip size (without, the Sig Sauer website points out pointedly, the use of replaceable backstraps) provides an outstanding convenience for an individual or family, where there may be different uses — concealed carry versus full-size competition shooting — and a variety of hand sizes. You can also imagine the advantages this system also provides for a large organization, such as a police department or the military, where missions differ and there’s a wide variety of hand sizes.
The P320 safety system is robust, to say the least. It is designed not only for protection against accidental discharge while carrying, but to make cleaning safer as well. First, there is a magazine interrupt safety; without the magazine in the well, the pistol will not fire. There is also a striker safety, to prevent the striker spring from releasing unless the trigger is pulled. The method of disassembly for cleaning ensures safety: the magazine must be removed, the slide has to be locked to the rear and the takedown lever is rotated (rather than manipulating the trigger).
Sig Sauer has been in the gunmaking business for over 150 years, and during that time they’ve developed the modular approach for many of their long guns — see their MPX SMG series. It was time for the modular system to be applied to handguns and, as much as traditionalists don’t like to admit it, that could best be done with a polymer grip/metal frame pistol. That Sig Sauer did it so well with the 320 series is a testament to their experience and vision.