11/24/2025 Brief history of the SR-25

 

 History of the SR-25

1. The Design & Designer

Designer: The SR-25 was primarily designed by Eugene Stoner, the legendary engineer who also created the AR-10 and AR-15 (M16).

Manufacturer: It is manufactured by Knight's Armament Company (KAC), which Stoner joined in the early 1990s and worked with its founder, C. Reed Knight Jr.

The Name: The name SR-25 is literally the sum of the numbers in Stoner's previous designs: AR-10 + AR-15 = 25.

Concept: Stoner sought to create a highly accurate, semi-automatic 7.62 mm rifle that could achieve the precision of a bolt-action rifle while offering the speed and follow-up shots of an auto-loader.

 

2. Design Foundation (Early 1990s)


AR-10 Revival: The SR-25 is essentially a heavily modified, modernized version of Stoner's original AR-10 (chambered in 7.62×51mm NATO).

Parts Commonality: It was engineered to have significant parts compatibility (up to 60% of parts) with the ubiquitous AR-15/M16, making logistics and maintenance easier.

Initial Configuration: The early commercial versions featured a long (up to 24-inch) heavy, free-floating match-grade barrel, which was key to its guaranteed sub-MOA (Minute of Angle) accuracy.

 

3. Military Adoption (Mk 11 Mod 0)

USSOCOM Interest: The US Special Operations Command (USSOCOM), particularly the U.S. Navy SEALs, took notice of the rifle's precision and semi-automatic capability. This allowed snipers to engage targets faster and more effectively than with traditional bolt-action rifles, especially in urban environments.


Official Adoption (2000): After a period of evaluation and modification (including shortening the barrel to 20 inches and adding a proprietary sound suppressor mount), the SR-25 was officially adopted by US Special Operations in May 2000 as the Mk 11 Mod 0 Semi-Automatic Sniper System.


Widespread Use: The Mk 11 Mod 0 saw extensive use in the Global War on Terror in Afghanistan and Iraq.

 

4. Further Evolution (M110 SASS)

U.S. Army Contract: The platform continued to evolve, and the U.S. Army later adopted a refined variant, also manufactured by KAC, known as the M110 Semi-Automatic Sniper System (SASS).


Modernization: Modern versions of the SR-25 (including the commercial and military Enhanced Match Rifle and Enhanced Combat Carbine variants) continue to improve the platform with ambidextrous controls, modern free-floating rail systems (like M-LOK), and enhanced bolt/carrier groups for greater reliability and durability.

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The SR-25 is widely credited with establishing the blueprint for the modern 7.62 mm semi-automatic Designated Marksman Rifle (DMR) platform used by militaries around the world.

 

Excellent video here with even more history and variations https://www.youtube.com/watch?v=yx7-CbkMJBk

 

Variations of the SR-25

 

  1. MK11
  2. M110 SASS
  3. M110K1
  4. extras