SIG Sauer P322 Rimfire Semiauto Pistol: Review

The .22 Long Rifle is one of the oldest cartridges still in use today, but despite its advanced age (the round first appeared in 1857), the ubiquitous .22 is still a popular choice for shooters of all skill levels. That’s why SIG’s engineers in New Hampshire have been hard at work developing a new semiauto .22 pistol, one that shares both the look and the reliability of the company’s centerfire semiautos. That rimfire repeater has finally arrived, and its name is P322.

As you might have guessed, the P322 shares a similar styling with the company’s P320 and P365 semiautos. The aluminum slide features front and rear slide serrations reminiscent of the brand’s centerfire models. The angular slide cuts that grow wider near the muzzle, which had become a signature styling touch on the P320 and P365, have also found their way to the P322. The control design and layout, grip orientation and other key features leave no doubt that the P322 shares the same SIG DNA with its centerfire cousins. Of course, the P322 uses an entirely different operating system. Like most .22s, it’s a blowback, hammer-fired gun that harnesses the recoil energy of the diminutive .22 LR cartridge to cycle a carefully weighted and balanced aluminum alloy slide.

Fixed-Barrel Accuracy

The barrel is fixed, which is one reason blowback .22s have the potential to be so accurate. Because the barrel doesn’t move each time the gun cycles, it remains consistently in position, and this consistency leads to smaller group sizes. A large mainspring surrounds the barrel. The big news with SIG’s little rimfire pistol, though, is capacity. This four-inch-barreled .22 semiauto ships with a pair of 20-round magazines. That’s more than Glock’s G44 .22, which comes standard with 10 rounds, or FN’s new 502 that offers both 10- and 15-round magazines. A SIG spokesman said plans are in the works to introduce 10-round magazines for those living in restrictive states or jurisdictions in the coming months. But for those who aren’t so limited, this gun’s impressive 20+1 capacity means lots of uninterrupted plinking time.

The P322’s polymer frame is similar to the P320, which means it features rather flat sides, a curved backstrap and a frontstrap with a generous undercut. SIG’s signature grip stippling pattern gives the gun a modern look, but it also offers a secure hold on the gun without being too aggressive. The magazine well is slightly flared, which aids reloads. The P322 chassis is made from stainless steel, and the slide moves smoothly on the rails. While there is a chassis, this is not a modular pistol.

Slide weight on this pistol is very light, so it’s great for shooters with limited hand strength. The P322 balances nicely, and at just 17 ounces unloaded, it is easy to carry and shoot. Red-dot optics are almost ubiquitous on today’s semiauto pistols, and the P322 comes with a slide that has been cut to accept red-dot sights. It works with SIG’s Romeo Zero sights, but others of similar size can be mounted using optics plates.

Optics Ready

Despite being an optics-ready pistol, the SIG P322’s open sights are very good. Both the rear and front sights have bright green fiber-optic inserts that gather light in dim conditions while remaining visible during bright midday sun. Texturing on the back of the rear sight cuts down glare. The front sight is removable, and so is the rear sight, which is integral to the optics cut plate. The rear is screw-adjustable for windage and elevation. An adjustment wrench is included in the box.

The P322’s trigger features a flat face that is easy to control and operate, but if you prefer more conventional trigger design, a curved trigger shoe is included in the box. The two triggers can be swapped quickly even with the slide in place, although SIG recommends removing the slide and magazine for safety. With the slide removed, maintain pressure on the front of the exposed hammer while pulling the trigger. This brings the trigger to an upright position, making it much easier to perform operations. From there, simply rotate and remove the trigger shoe and replace it. SIG offers several how-to videos on operating the P322, and one of these demonstrates this process. In addition to these videos, SIG provides a written manual with the firearm that is easy to understand and follow.

One of the SIG P322 videos addresses loading, and while that may seem elementary, it’s worth discussing because many of the murmurings about the P322’s reliability stem from one issue: improperly seating rounds in the magazine. There are lateral tabs on either side of the magazine that assist in compressing the internal spring. The temptation is to depress the tabs and start dropping .22 rounds into the magazine, but this can cause the cartridges to align improperly, resulting in stoppages while firing.

Instead, compress the mag spring just enough to add a single cartridge to the stack. A loading tool is provided to assist in this operation. Doing so maintains order in the magazine stack and results in proper cartridge alignment—and proper function. As you’ll later read, properly loading the gun allows the P322 to run reliably, so if you run into feeding issues—as I did before realizing what I’d done wrong—the first order of business is to be certain the ammo is properly oriented in the mag. The P322 no doubt will serve as a training gun for the P320 and its military counterparts, the M17 and M18, and the P322 is well suited to that role. It even fits some P320 holsters.

The control layout among these guns is quite similar, and the P322 features a takedown lever, an ambidextrous slide stop and an ambidextrous manual safety. The P322’s magazine release is triangular and positioned just above the undercut on the trigger guard—similar to the P320/M17/M18 pistols. The unloaded P322 weighs just eight ounces less than the similar-size 9mm P320 compact Nitron. Height and sight radius are within 0.2 inch on both pistols, and the ergonomics are so similar that a shooter trained on the P322 will have no problem transitioning to the Nitron or other SIG guns like the P365XL. The light-recoiling P322, with its low-cost ammunition, will help keep experienced shooters tuned.

In preparation for range testing, I removed the SIG’s muzzle cap and replaced it with the threaded adapter so that I could shoot the gun with my Banish 22 suppressor in place. I appreciate SIG’s attention to detail and sense of styling, so it’s no surprise that the company included a threaded barrel and thread protector that remain hidden when the gun is in use. Threaded barrels with knurled thread protectors that extend beyond the muzzle look garish to me despite their convenience. Be aware that the SIG P322 should not be disassembled without either the thread protector or the adapter in place. The spring rests on these, so having them in place keeps the spring contained during fieldstripping. It’s not a catastrophe if you fail to have either the adapter or the thread protector in place, but it’s a decision you’ll regret.

At The Range

I usually begin shooting tests with a few warm-up rounds to familiarize myself and make initial observations and then go directly into accuracy testing. Such was not the case the P322. With a magazine full of ammunition and a collection of spinning and stationary targets in front of me at the range, I went right to work with the SIG, running those cavernous polymer magazines dry in short order. I remember testing the discontinued SIG Mosquito, which struggled to function with a full range of .22 ammo, but that’s not the case with the P322. With a properly loaded magazine, it sends one shot after another, punching neat .22 holes and keeping the spinners operating. On a scale of one to fun, the SIG certainly ranks near the top.

I also appreciate this gun’s versatility. I could use either iron sights or my Romeo Zero sight, and I could shoot the pistol with or without a can in place. When the suppressor is installed, this gun is whisper quiet—especially with mild .22 match ammo. Even the most noise-sensitive neighbors won’t be irritated by the snick of the P322 with subsonic ammo, and there was just one malfunction with a suppressor and light target ammo. I swapped out trigger shoes, decided that the flat-face design was my favorite, and switched back. If you’re shooting offhand, you’ll enjoy the SIG’s reliable 3.25-pound pull, as tested on my Wheeler gauge.

From the bench, I realized that the trigger has pull has three distinct phases. There’s a very light initial take-up before the trigger becomes noticeably, though not dramatically, heavier. There’s additional tightening at the break point, beyond which minimal movement and pressure are required to trip the sear and drop the hammer. Trigger reset is short with audible and tactile indicators, and the P322 is an ideal tool to practice shortening your trigger stroke for faster follow-up shots.

My primary complaint with the P322 has nothing to do with the gun itself. I just wish that the included case was large enough to accommodate the gun with an optic in place. I transferred the P322 to an MTM case while traveling to and from the range, and that allowed me enough space to store extras like the suppressor, spare trigger shoe, magazine loader, manual and more with room to spare. Accuracy was impressive, with five-shot groups as small as 1.5 inches using SK’s Pistol Match ammunition. With affordable Winchester bulk ammunition, the pistol managed a group of 2.9 inches, and average group size was between about 2.0 and 3.5 inches when fired from the bench at a range of 25 yards.

Reliability was also very good with a full range of ammunition ranging from 850 fps target loads to faster varmint hunting ammo, and I had just two failures to feed during over 100 rounds of testing. The slide locked back as the last round was fired from each magazine, which isn’t always the case with all .22 semiauto blowback pistols. The magazine drops free when the release is depressed, although not with the authority of a metal magazine.

Over my career as a gun writer, I’ve come to dislike the lilliputian controls on some semiauto pistols. The SIG’s controls aren’t outsize, but they’re large enough that you can easily operate the gun. The slide serrations are aggressive enough to allow full control during manipulations, and the flared mag well allows for faster and more precise reloads. I think SIG leads the semiauto pistol pack regarding ergonomics, and the P322 is a good-looking gun that feels great in the hand. With a suggested retail of $479, the SIG competes with the FN 502 Tactical ($519) and Taurus TX22 Competition ($533)—especially considering that the P322 boasts a higher capacity than either of those guns.

While the SIG Sauer P322 is indeed a great training gun, it’s much more than that. The easy-to-operate design, light weight and scant recoil make it a sensible pistol for new shooters. Whether you’re new to firearms or a seasoned IPSC competitor, you can’t deny that the P322 is a fun gun to shoot, a blowback pistol that gobbles up low-cost ammunition and brings smiles to the faces of all who spend time behind it.

SIG Sauer P322 Specs

• Type: Blowback-operated, semiauto rimfire
• Caliber: .22LR
• Capacity: 20+1 rds. 
• Barrel: 4 in. 
• OAL/Height/Width: 7/5.5/1.4 in. 
• Weight: 17.1 oz. 
• Construction: Black anodized aluminum slide, black polymer frame
• Trigger: 3.3 lbs. pull (tested) 
• Sights: Fiber-optic rear on optics plate, fiber-optic front; ROMEOZero footpring
• MSRP: $479
• Manufacturer: SIG Sauer

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