Mk 11 Mod 0
Knight's Armament Company · Sniper Rifle · In Production · 2000
Also known as: Mk 11 SWS, Mk 11 Sniper Weapon System, SR-25 Mk 11, Navy SEAL Sniper Rifle
Overview
The Mk 11 Mod 0 is the United States Navy's designation for the militarized version of the Knight's Armament SR-25, adopted as a semi-automatic sniper system for Navy SEAL sniper teams and Marine Corps scout snipers. Based on Eugene Stoner's innovative AR-10-derived design, the Mk 11 Mod 0 combines the ergonomics and manual of arms of the M16/M4 family with the extended range and power of the 7.62x51mm NATO cartridge. The rifle features a 508mm (20-inch) match-grade barrel, direct impingement gas system, and a free-floating handguard for maximum accuracy. The Mk 11 was specifically configured for the sniper role with a two-stage match trigger, suppressor-compatible flash hider, and optics rail. Adopted in 2000, the Mk 11 Mod 0 saw extensive combat use in Afghanistan and Iraq, where its combination of semi-automatic fire and precision accuracy made it invaluable for urban and rural engagements alike. The system was designed to be suppressor-compatible from the outset, and was frequently deployed with the KAC NT4 QD suppressor.
Specifications
| Weight (empty) | 4880 g (172.1 oz) |
| Weight (loaded) | 5500 g (194.0 oz) |
| Overall Length | 1118 mm (44.02") |
| Barrel Length | 508 mm (20.00") |
| Action Type | Gas Operated Direct Impingement |
| Firing Mechanism | Hammer Fired |
| Trigger Type | Two Stage |
| Trigger Pull | 22 N (4.9 lbf) |
| Magazine Capacity | 20 rounds |
| Magazine Type | Detachable Box |
| Muzzle Velocity | 838 m/s (2749 fps) |
| Muzzle Energy | 3336 J (2461 ft·lbf) |
| Effective Range | 800 m (875 yd) |
| Maximum Range | 2800 m (3062 yd) |
| Barrel Rifling | Right Hand |
| Rifling Twist | 292 mm (11.50") |
| Number of Grooves | 6 |
| Frame Material | Aluminum Alloy |
| Barrel Material | Match Grade Stainless Steel |
| Stock Material | Polymer Composite |
| Finish | Matte Black |
Calibers
- 7.62x51mm NATO · primary · 7.62x51mm NATO — also known as .308 Winchester, 7.62mm NATO, 7.62x51mm
Features
- Firing modes: Semi Automatic
- Feed systems: Detachable Box Magazine
- Safety mechanisms: Manual Safety, Firing Pin Safety
- Features: Free Floating Barrel, Match Grade Barrel, Accessory Rail, Free Floating Handguard, Flash Hider, Suppressor Ready
Variants
- Mk 11 Mod 1 — Improved
- Mk 11 Mod 2 — Improved
Base model
Service history
Operators
- United States Naval Special Warfare (Navy SEALs) · adopted 2000
- United States Marine Corps · adopted 2001
- United States Navy · adopted 2000
- United States Special Operations Command · as Mk 11
Conflicts
- War in Afghanistan (2001-2021)
- Iraq War (2003-2011)
- War on Terror (Global) (2001-present)
Production
Production years: 2000-present
Production numbers classified. Manufactured by Knight's Armament Company under military contract for US Naval Special Warfare and Marine Corps procurement.
Origin
Country of origin: United States
Designer: C. Reed Knight Jr.
Notes
The Mk 11 Mod 0 is essentially an SR-25 Match Rifle configured to Navy specification, including specific trigger, handguard, flash hider, and suppressor compatibility requirements. The rifle was originally procured under the Naval Special Warfare Sniper Rifle program. Standard issue paired the Mk 11 with a Leupold Mk 4 3.5-10x40mm scope. The Mk 11 was gradually replaced by the Mk 20 SSR (SCAR-H PR) and the M110 SASS in various US military roles, though some units retained the Mk 11 for its lighter weight and proven reliability. The direct impingement gas system, while requiring more frequent cleaning than piston alternatives, was valued for its inherent accuracy advantage due to reduced reciprocating mass.
Background
The Mk 11 Mod 0 earned its legendary reputation in the hands of Navy SEAL snipers during the early years of the War on Terror. The rifle was favored for its ability to deliver rapid, accurate semi-automatic fire in situations where bolt-action rifles like the M40 were too slow. In the Battle of Ramadi (2006), SEAL snipers used the Mk 11 extensively from overwatch positions, exploiting its suppressed capability to engage targets without revealing their positions. The rifle's SR-25 heritage, designed by the legendary Eugene Stoner, made it the first truly successful semi-automatic sniper system in US military service.