The Secret Service Duty Rifle Build: A Detailed Breakdown

Only the best equipment will suffice when protecting the president of the United States.

The Knight’s Armament SR-16 (allegedly used by the Secret Service) is a great example of modern duty rifles.

With two distinct configurations tailored to the agency’s needs, these rifles showcase precision engineering and uncompromising performance.

Two Variants of the Secret Service SR-16

The Secret Service employs two main configurations of the SR-16, each optimized for specific mission requirements. Here’s a detailed look at these builds:

Gen III SR-16 E3 CQB

This variant features a compact 11.5” upper receiver, making it highly maneuverable for close-quarters engagements. Here’s the breakdown:

Upper Configuration:

• Upper Receiver: SR-15/16 E3 CQB Gen III 11.5” Upper Receiver
• Rail System: KAC URX 2 Mid-Length
• Charging Handle: KAC Charging Handle
• Bolt Carrier: KAC Phosphate Carrier
• Front Sight: URX 2 Integral
• Rear Sight: KAC 600 Meter or KAC 600 Meter Micro
• Optics: Aimpoint T-1/2 or Aimpoint Comp M2/3
• Optic Mount: LaRue LT-660, Factory Mount (T-1), Wilcox P/N 13600G01 (Comp M2), or KAC 30mm Aimpoint Comp Mount P/N 98073-1 (Comp M2)
• Magnifier: Aimpoint 3x
• IR Laser: Steiner D-BAL A3 or Insight TPIAL (AN/PEQ-2A), or Black/Tan Insight ATPIAL (AN/PEQ-15)
• Light: Insight M3X (Incandescent or LED Module) or Streamlight TLR-1 HL
• Muzzle Device: KAC NT4-QDSS Flash Hider
• Handguard Accessories: KAC 11-Rib Rail Cover Panels, LaRue FUG, KAC Forward Pistol Grip

Lower Configuration:

• Lower Receiver: Complete QD Cup SR-15 IWS Lower or Newer SR-15 IWS Lower
• Trigger: KAC 2-Stage
• Pistol Grip: KAC A2, Magpul MIAD, or Magpul MOE
• Stock: Black LMT SOPMOD or Black Magpul CTR
• Sling: Black Blue Force Gear Vickers, VTAC, or Magpul MS3

MOD 1 SR-16 E3 CQB

The MOD 1 variant introduces the URX 3.1 rail system, a refined option for enhanced ergonomics and accessory mounting. The optic options also expand to include LPVOs like the Vortex Razor HD.

Upper Configuration:

• Upper Receiver: SR-15/16 E3 CQB MOD 1 11.5” Upper Receiver
• Rail System: KAC URX 3.1 (10.75”)
• Charging Handle: KAC Charging Handle
• Bolt Carrier: KAC Phosphate Carrier
• Optics: Aimpoint T-1/2, Aimpoint Comp M2/3, or Vortex Razor HD Gen II 1-6×24
• Front Sight: KAC Micro
• Rear Sight: KAC 600 Meter Micro
• Optic Mount: LaRue LT-660, Factory Mount (T-1), Wilcox P/N 13600G01 (Comp M2), or KAC 30mm Aimpoint Comp Mount (Comp M2)
• Magnifier: Aimpoint 3x
• IR Laser: Black/Tan Insight ATPIAL (AN/PEQ-15)
• Light: Insight M3X (Incandescent or LED Module) or Streamlight TLR-1 HL
• Muzzle Device: KAC NT4-QDSS Flash Hider
• Handguard Accessories: KAC URX 3.1 Panels & Handstops

Lower Configuration:

• Lower Receiver: Complete QD Cup SR-15 IWS Lower or Newer SR-15 IWS Lower
• Trigger: KAC 2-Stage
• Pistol Grip: KAC A2, Magpul MIAD, or Magpul MOE
• Stock: Black LMT SOPMOD or Black Magpul CTR
• Sling: Black Blue Force Gear VCAS, VTAC, or Magpul M3/4
• Lower Accessories: Optional Law Tactical Gen 3 Folder

Exclusive Features of the Secret Service Rifle

Beyond the individual build configurations, the SR-16 incorporates several advanced features that make it a standout choice for elite operators:

Proprietary Rail System

The FF RAS (Free Float Rail Adapter System) is unique to the Secret Service. This rail is not available to any other government contracts or civilian markets, showcasing Knight’s Armament’s commitment to custom-tailored solutions. The FF RAS enhances stability, precision, and modularity, making it ideal for mounting mission-specific accessories.

Sand Cutter Bolt Carrier Group

This bolt carrier group is designed for adverse environments, featuring debris channels to ensure seamless operation in dirt, sand, or dust. The hard chrome finish improves durability and allows the carrier to hold oil and lubricant better, enabling longer intervals between maintenance cycles.

Ambidextrous Controls

Designed for maximum usability, the SR-16 includes:

• Ambidextrous Bolt Release
• Ambidextrous Magazine Release
• Ambidextrous Safety Selector
• Ambidextrous Charging Handle

These features make the rifle user-friendly for right- and left-handed operators, ensuring adaptability in high-stress environments.

The SR-16 in Action

This rifle is designed to excel in environments where precision and reliability are paramount. For the Secret Service, its primary use likely involves close-quarters protection and urban environments. Its compact design and lightweight profile make it easy to maneuver in tight spaces, while its accuracy ensures mission success when seconds count.

Why the Secret Service Chooses Knight’s Armament

Knight’s Armament rifles are renowned for their precision, reliability, and build quality. Here’s why they’re a preferred choice for elite units:

• Durability: Designed to handle high round counts with minimal wear and tear.
• Exclusivity: Custom-built components like the FF RAS rail are not available elsewhere.
• Performance: From optics to suppressors, every accessory on the SR-16 is optimized for mission success.

Final Thoughts

The Knight’s Armament SR-16 is a testament to what’s possible when no compromises are made in design and functionality. Used by the Secret Service, it’s not just a tool—it’s a symbol of readiness, precision, and the elite standards of those who wield it. While most will never own this rifle, its features and engineering inspire enthusiasts and professionals to aim for the best.

Whether you’re looking to build a similar setup or just appreciate the engineering marvel, the SR-16 exemplifies what’s possible in modern firearms design.