M11: A U.S. military designation for the Sig Sauer P228

The M11, a US military designation for the SIG Sauer P228 pistol, has garnered significant attention since its adoption by the US military in the

Eric Sof

Sig Sauer M11 with TLR-1 flashlight attached
Sig Sauer M11 with TLR-1 flashlight (Photo: XY)

The M11, a US military designation for the SIG Sauer P228 pistol, has garnered significant attention since its adoption by the US military in the early 1990s. Primarily issued to Military Police, Naval Aviation, Military Criminal Investigation Command, and other units requiring a compact and discreet handgun, the M11 quickly became popular among civilian customers. This article delves into the features, design, and variants of the M11 compact pistol, highlighting its significance and exploring its replacement, the M18.

Design and Operation

The SIG Sauer P228, known as the M11 in military service, is exclusively chambered for the 9×19 mm Parabellum ammunition. Built with a short recoil system, the pistol employs the well-known modified Browning locked-breech design, a feature shared among all SIG Sauer P-series locked breech pistols. The locked breech operation ensures reliability and consistent performance.

SIG Sauer P228 with flashlight attached on Picatinny rail
SIG Sauer P226 with a flashlight attached on Picatinny rail (Photo: XY)

Trigger Options and Safety Features

The M11 is available in two trigger configurations: double action (DA) or double action only (DAO). The pistol incorporates a built-in firing pin safety to enhance user safety, eliminating the need for manual safeties. A decocking lever is also positioned on the left side of the frame. It is important to note that the DAO version lacks a decocker. Nevertheless, the M11 allows for secure carry with a loaded chamber, ensuring readiness when needed.

Frame Options and Magazine Compatibility

The compact M11 pistol offers two frame variants: a standard aluminum frame and a stainless steel frame. The aluminum frame version, weighing slightly less, provides users an option based on their preferences and requirements.

The M11 is fed through double-stack magazines with a 13-round capacity. Notably, it also accepts 15- or 20-round magazines designed for the full-size SIG Sauer P226 pistol, expanding its versatility and ammunition capacity. The magazine release button is reversible, accommodating both right-handed and left-handed users.

Durability and Reliability

The M11 has gained a reputation throughout its service life for its durability, reliability, and exceptional craftsmanship. This compact pistol has withstood rigorous testing and has consistently demonstrated its ability to withstand demanding military environments. The M11’s robust construction ensures its reliability in critical situations.

M18 Pistol: A Modular Successor to the M11

Recently, the US military introduced the M18 compact pistol to replace the M11. The M18 is a compact version of the SIG Sauer P320 and employs the same 9×19 mm Parabellum ammunition as its predecessor. However, the M18 was designed as a modular multi-caliber weapon, offering adaptability to various calibers, including .40 S&W, .375 SIG, .380 ACP, and .45 ACP. SIG Sauer provides conversion kits for the M18, allowing straightforward caliber changes by replacing barrels, slides, frames, and magazines. Adoption of the M18 has occurred across the US Army, Air Force, Navy, and Marine Corps, with production commencing in 2017 or 2018. Over the next decade, the M18 will gradually replace the M11 in US military service.



Alongside the military model, a commercial variant of the M11 exists, known as the M11-A1. This commercial version possesses several distinctions from its military counterpart, as it is exclusively sold to the government. The M11-A1 features a stainless steel slide and a larger grip, accommodating a more comfortable hold for users. Unlike the standard M11, the M11-A1 utilizes 15-round magazines, providing additional ammunition capacity. While these differences may seem minor, they cater to different users’ specific needs and preferences, whether in military or civilian contexts.

M11-A1 version of the Sig Sauer P228
M11-A1 version of the Sig Sauer P228 (Photo: XY)


The M11 compact pistol, also known as the SIG Sauer P228, has carved a place in military and civilian firearms. Its adoption by the US military and subsequent popularity among various units speak to its reliability, durability, and compact design. With options for different frame materials, trigger configurations, and magazine compatibility, the M11 offers versatility to meet individual requirements.

However, as technology advances, the US military has embraced the M18 as a successor to the M11. The modular design of the M18, based on the SIG Sauer P320, allows for easy caliber conversions, catering to different mission needs and ammunition availability. The gradual replacement of the M11 by the M18 in US military service reflects the commitment to innovation and adaptability.

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

Whether in military or civilian hands, the SIG Sauer P228/M11 compact pistol has proven its worth as a reliable and well-made firearm. Its durability and performance track record ensure its place as a trusted sidearm. Meanwhile, the introduction of the M18 demonstrates the constant evolution of firearms technology to meet the changing demands of modern warfare and personal defense.

Technical specifications

Country of origin:United States
Manufacturer:SIG Sauer
Caliber:9×19 mm
Weight (empty):825 g
Length:180 mm
Barrel length:99 mm
Muzzle velocity:?
Magazine capacity:13 rounds
Sighting range:?
Range of effective fire:~ 30 m

Eric Sof

Eric Sof holds a master's degree in Political Science, specializing in International Peacekeeping Studies. He has over a decade of experience as a former member of an elite counterterrorism unit. Additionally, he is a firearms instructor and currently serves as a member of the SWAT unit.

Related Post

1 thought on “M11: A U.S. military designation for the Sig Sauer P228”

  1. Wow! This is a joke, right? You talk about the M11 (P228), and all you showed are pics of the P226 (MK25). How embarrassing. Smh.

Leave a Comment