The very latest version of the P320 lands with some innovations never seen before

credit: Archant

SIG’s P320 semi-automatic-style pistol still feels new to me, although it’s been with us for a while now and has become available in a number of options. They have a good heft and feel, which SIG claims is an exact replica of the cartridge-firing variants, and they should know because they manufacture both. There’s an obvious rugged appeal; these handguns were designed for hard military use from day one and SIG recently won a very hard-fought selection competition to supply their M17 model to various elements of the American Army. This brings huge kudos and on the back of this SIG has released civilian variants in countries that allow private ownership of powder-burning handguns.

For the rest of us, they developed the CO2-powered version you see on test, which looks identical, unsurprisingly. They chose to copy the extended 21 round, 9mm magazine which makes space for an innovative CO2 loading mechanism. The mag’ extends some 1¼” below the grip and that adds an unusual look to the pistol, although I didn’t notice it affecting the handling at all.

credit: Archant

The grip and frame are made from a tough industrial polymer and I found the ergonomics spot on for my medium-sized hands. Coming on aim as fast as I could in a two-handed combat hold, the sights aligned perfectly with no need for corrections to the angle. The grip filled my palm nicely and I noted no sharp edges or rough spots to cause soreness during long sessions. One of the Army requirements was for an ambidextrous, manual safety and although the one fitted to my test gun was stiff, it was well placed to be disengaged nicely as I addressed the targets. In front of this is a dummy slide release lever. These and the take-down lever are black, contrasting against the coyote tan frame and slide.

Well developed

On top we find some bold, combat-style sights which are non-adjustable. They show the well-proven ‘three white dot’ system that I particularly like, and have a good notch to post ratio that makes fast targeting easy. The service arm bought by the Army has a removable panel in front of the rear sight that exposes a rail to accept an optical sight. On the CO2 model this is just a dummy cover, but keeps the replica appearance correct. I think it’s a shame because I can well imagine buyers wanting to add a red-dot sight to this pistol.

credit: Archant

Despite its blow-back action, this is a double-action only trigger because the first stage of the trigger’s movement drives the Rapid Pellet Magazine (RPM) around to align the next pellet with the barrel. The second stage drops the hammer and allows the CO2 to flow from the valve and drive the pellet down the barrel. The packaging says ‘semi-auto’, when it’s in fact a type of revolver in its function. I’ve used the RPM in pistols and sub-machine gun variants, and I’ve yet to have a jam or a problem, showing that it was a well-developed product as it was released. It takes a while to load 20 .177 pellets into the belt, but it’s an easy job.

Army selection

The sturdy magazine also holds the 12 gramme CO2 capsule and that interesting loading mechanism. At the rear, there’s a lever that you drop back to begin and then slip a capsule in bottom first. Pressing the lever shut drives the capsule onto the piercing probe which holds the pressure until the mag’ is loaded into the action. A second probe then enters the mag’ allowing the gas to flow into the valve. This means that if you remove the mag’, the pistol is completely safe because it contains no gas or pellets. I was concerned that the loading lever might snag off the back of the magazine well during fast reloads, but it never did.

credit: Archant

On the range, I found the sights excellent and the trigger smooth and consistent. You must remember to allow the trigger blade to go fully forward after each shot is released, to index the magazine again. If you don’t, the pistol will not fire and this makes fast double-taps somewhat tricky, but goes unnoticed in slower paced shooting. There’s no exposed hammer, so you cannot cock the action and fire single action, but that’s not what a soldier needs, so it’s not what SIG designed.

The blow-back movement of the slide is quite short and not that punchy, which makes keeping the sights on target much easier than with some pistols. I found the sights where slightly low and right for my eyes at six yards, but would easily hit an IPAS competition target plate. Only at longer distances did I need to adjust my aim point. This is clearly another winner for SIG, and knowing this is the pistol that won a tough army selection is sure to make it all the more desirable.


Manufacturer: SIG Sauer Inc

Importer: Highland Outdoors


Model: P320 M17

Type: CO2

Action: Blow-back

Length: 8”

Weight: 2.2lbs

Trigger: Double-action only

Magazine capacity: 20

RRP: £199.99

Mag: £34.99

Twin pack belts: £21.99


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