Sig Sauer P320: A new United States Armed Forces service pistol

Sig Sauer P320 United States Armed Forces service pistol
Sig Sauer P320 (Photo: Sig Sauer Inc.)

The SIG Sauer P320 is chosen as successor to the Beretta M9, a former the United States Armed Forces service pistol. Unlike the M9, P320 is a modular semi-automatic pistol. The pistol was manufactured by SIG Sauer, its American branch, in 2014 when it entered the market. Real attention it got in 2017 after winning the XM17 Modular Handgun System competition.

The competition organized by the United States Armed Forces was looking for the next service pistol, and actually, slightly customized Sig Sauer P320 won the competition.


The exciting concept of the Sig Sauer P320 is elegant, though the Europeans would benefit from the chassis system. The Sig Sauer P320 can be chambered in 9×19mm Parabellum, .357 SIG, .40 S&W, and .45 ACP, and can be easily converted from one caliber to another; a change from .357 SIG to .40 S&W requires only a barrel change; a difference between 9mm to .357 SIG or .40 S&W and vice versa are accomplished using a caliber exchange kit.

The Sig Sauer P320 was designed to be ambidextrous in handling, sporting a catch lever on both sides of the slide and user-reversible magazine release. All other operating controls are designed to be operated from either side. The firearm can be field stripped with no tools. Additionally, the firearm can also be field stripped without depressing the trigger, an additional safety feature to prevent negligent discharge of the weapon. The fire control unit is removable, allowing to switch to different frame sizes.

The P320 trigger shoe is available as an all-metal, solid trigger. And yes, I forgot to mention it’s a staple 9mm striker-fired handgun of excellent quality. In comparison with Beretta M9, it is a better firearm. Lighter, adaptable, has good sights and is cheaper than the M9.

SIG Sauer P320 fire control unit with trigger
SIG Sauer P320 fire control unit with trigger (Photo: Sig Sauer)


X series

The X Series lineup includes the following grip module sizes:

  • Carry size – Fits any SIG P320 compact-size slide in 9mm, .40 S&W, and .357 SIG. The full-size slide also fits the carry-size grip module without any part of the recoil spring show.
  • Full size – Fits any SIG P320 full-size slide in 9mm, .40 S&W, and .357 SIG.
  • Compact size – As of March 2020, the P320 XCompact is available in 9mm only.
SIG Sauer P320 Compact
SIG Sauer P320 Compact (Photo: Sig Sauer)

XFive Legion

Released in late July/early August 2019, the XFIVE Legion is considered the flagship of the P320 platform that brings added weight and features. The TXG grip module has tungsten infused directly into the polymer along with an attachable magazine well. It comes standard with Henning group aluminum base pads and a skeletonized flat trigger. The complete 9mm slide is cut and ported to reduce weight and assist recoil and feeding abilities. It also has a slide plate for optic capabilities.


The SIG P320MAX is a sporterized variant of the P320, designed in 2021 for competition shooters. The pistol comes with ROMEO3 MAX sights, and the tungsten-infused TXG heavy grip module weighs 43.5 oz (1.23 kilograms), has a 5-inch (130 mm) match-grade barrel, and an overall length of 8.5 inches (220 mm).


On 19 January 2017, it was announced that a customized version of the SIG Sauer P320 had won the United States Army’s XM17 Modular Handgun System competition. The full-sized model will be known as the M17, and the carry-sized model will be known as the M18.

Sig Sauer P320 PRO Series
Sig Sauer P320 PRO Series (Photo: Sig Sauer)

It beat Glock, although the Glock is already adopted by other European anti-terrorist units, including the SAS and GSG 9. Those units mostly adopted Glocks in preference to other pistols, including H&Ks and SIG Sauers. Even GIGN is likely to carry a Glock instead of (or sometimes as well as) their signature MR 73 revolver.

Not only can those units be considered as expert users, as are the USMC Raiders and Navy Seals, but they also have the operational freedom to adopt whichever weapons they consider most effective.

Technical specifications

Manufacturer: SIG Sauer Inc., Exeter, New Hampshire, U.S.;

SIG Sauer GmbH, Eckernförde, Germany

Type: Short recoil-operated, locked-breech SIG Sauer System, semi-automatic
Caliber:  9×19mm Parabellum, .357 SIG, .40 S&W, and .45 ACP
  • 120 mm (4.7 in) P320 Full Size
  • 98 mm (3.9 in) P320 Carry
  • 98 mm (3.9 in) P320 Compact
  • 91 mm (3.6 in) P320 Subcompact
  • 833 g (29.4 oz) P320 Full Size (incl. magazine)
  • 737 g (26.0 oz) P320 Carry (incl. magazine)
  • 737 g (26.0 oz) P320 Compact (incl. magazine)
  • 708 g (25.0 oz) P320 Subcompact (incl. magazine)
Magazine capacity:
  • 10 rounds .45 ACP
  • 14 rounds .357 SIG, .40 S&W
  • 17 rounds 9×19mm Parabellum


  1. If my life depended on a P320 in action, i would rather use a bow and arrow because the P320 which i have used at the Stittsville shooting range and i could never hit a 2FT target at 25 yards, in winter condition, making this gun unreliable for defence unless you are using it within a 2 to 3 yards distance!!!
    Yours truly


Please enter your comment!
Please enter your name here