Mk 11 Mod 0
- Category
- Sniper Rifle
- Barrel
- 508 mm
- Weight, empty
- 4.88 kg
- Introduced
- 2000
About
What it is, and why it matters
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.
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.
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.
Specification
Everything measured
IdentityWhat it is, who built it and when.
- Manufacturer
- Knight's Armament Company
- Category
- Sniper Rifle
- Country
- United States
- Status
- In production
- Produced
- 2000
- Variant of
- Military designation
DimensionsAs issued, without a magazine or an optic.
- Barrel
- 508 mm
- Overall length
- 1118 mm
- Weight, empty
- 4.88 kg
- Weight, loaded
- 5.50 kg
ActionHow it cycles, what trips it, and what feeds it.
- Action
- Gas operated direct impingement
- Firing mechanism
- Hammer fired
- Trigger
- Two stage
- Trigger pull
- 22.0 N
- Capacity
- 20
- Magazine
- Detachable box
MaterialsEach swatch is the material itself, not a colour chosen to stand for it.
- Frame
- Aluminum alloy
- Barrel
- Match grade stainless steel
- Stock
- Polymer composite
- Finish
- Matte black
BallisticsFrom the service cartridge, not a handload.
- Muzzle velocity
- 838 m/s
- Muzzle energy
- 3336 J
- Effective range
- 800 m
- Maximum range
- 2800 m
Trajectory
What the round does downrange
Solved from the muzzle figures and the bullet. The dashed rule is the effective range on the record, and the crosses are the steps the solver returned.
Features
What it has
What the record lists as fitted, drawn from the catalogue.
Free floating barrel
Match grade barrel
Accessory rail
Free floating handguard
Flash hider
Suppressor ready
Standing
How it compares
Each figure against the firearms of the same type and cartridge that record it, or of the same type where that cartridge has too few. Positions are read to the nearest tenth.
| Measurement | This firearm | Median | Position |
|---|---|---|---|
| Empty weightAmong 80 7.62x51mm NATO sniper rifles | 4.88 kg | 5.04 kg | Lighter than about 60% |
| Overall lengthAmong 80 7.62x51mm NATO sniper rifles | 1118 mm | 1116 mm | Longer than about 60% |
| Barrel lengthAmong 80 7.62x51mm NATO sniper rifles | 508 mm | 559 mm | Shorter than about 60% |
| Magazine capacityAmong 80 7.62x51mm NATO sniper rifles | 20 | 15 | Holds more rounds than about 80% |
Answers
Questions about the Mk 11 Mod 0
How much does the Mk 11 Mod 0 weigh?
The Mk 11 Mod 0 weighs 4.88 kg (10.76 lb) empty and 5.50 kg (12.13 lb) loaded.
What caliber is the Mk 11 Mod 0?
The Mk 11 Mod 0 is chambered in 7.62x51mm NATO.
How many rounds does the Mk 11 Mod 0 hold?
The Mk 11 Mod 0 holds 20 rounds, fed from a detachable box magazine.
How long is the Mk 11 Mod 0?
The Mk 11 Mod 0 is 1118 mm (44.0 in) long overall, with a 508 mm (20.0 in) barrel.
Who makes the Mk 11 Mod 0?
The Mk 11 Mod 0 is made by Knight's Armament Company (United States). It was designed by C. Reed Knight Jr..
When was the Mk 11 Mod 0 introduced?
The Mk 11 Mod 0 was introduced in 2000.
How does the Mk 11 Mod 0 operate?
The Mk 11 Mod 0 uses a gas operated direct impingement action, and its firing mechanism is hammer fired.
Compatibility
Which parts fit this firearm
Studio
Every part that mounts on this, resolved
Not a list the maker typed out: the answer comes from the mounts this firearm exposes and the interface each part needs, so it stays right when either one changes.
- Every part that mounts on any firearm in the catalogue
- Interface standards, platforms and fit overrides
- The same answers through the API and the MCP server
Requires a signed-in GunSpec account on the Studio plan. The answer is computed per part, so it is not part of the public record.
Provenance
What the record holds
Every figure above was taken from one of these pages. The confidence reflects how much of the record came from a page a claim can be checked against.
In service
- United States Naval Special Warfare (Navy SEALs)
- 2000
- United States Marine Corps
- 2001
- United States Navy
- 2000
- United States Special Operations Command
- United States
Provenance
Confidence in this record
80%
Stockists
Where to buy
Offers link straight to the shop. GunSpec never takes the order.
No shop has listed this firearm yet
Stock and prices come from the shops themselves. If you sell this firearm, you can list it and it appears here.
List a firearmMCP
Ask an assistant about it
The same record, reached the way a person asks for it rather than the way a program does.
Ask GunSpec
Works with
Point an MCP client at GunSpec and it answers from the catalogue rather than from memory. A free key covers the read tools.
API
The call that returns this record
The same fields, in the same units, from the same endpoint the page reads.
curl --request GET \ --url 'https://api.gunspec.io/v1/firearms/mk-11-mod-0' \ --header 'X-API-Key: your_key'{ "id": "mk-11-mod-0", "name": "Mk 11 Mod 0", "manufacturer": { "id": "knights-armament", "name": "Knight's Armament Company", "countryCode": "US", "foundedYear": 1982, "website": "https://www.knightarmco.com", "logoUrl": null, "description": null, "status": null, "defunctYear": null, "stateOwned": null, "makesFirearms": null, "parentId": null, "predecessorId": null, "createdAt": "2026-02-11 23:44:38", "updatedAt": "2026-02-18 03:40:45", "version": "0b3c3f0a0149c800488fc669f0c106012c0171e0595be976331646ae4580d317" }, "category": { "id": "sniper-rifle", "name": "Sniper Rifle", "description": "Precision rifles optimized for long-range accuracy" }, "country_of_origin": "US", "year_introduced": 2000, "barrel_length_mm": 508, "weight_empty_g": 4880, "action_type": "gas_operated_direct_impingement"}