Knights Armament Sr-25 K5 7.62 Nato/.308 14.5'' Bbl Assembled Upper Rcvr Black

The Knights Armament SR-25 K5 assembled upper receiver brings precision rifle capability to the .308/7.62 NATO platform in a 14.5-inch configuration. Built as the commercial variant of the military M110K5, this upper is engineered for shooters who need effective performance from close quarters out to 800 meters—whether you're running a precision rifle build, a modern sporting rifle project, or a dedicated .308 AR platform. The SR-25 K5 represents the latest generation of Knights Armament's dual-role carbine design, combining rugged reliability with ergonomic refinement and genuine modularity.

What sets this upper apart is attention to the details that matter in the field. The high-pressure dual-ejector bolt cycles reliably in suppressed and unsuppressed configurations, even in tough conditions, and benefits from an extended service life. Fully ambidextrous controls—including charging handles and selector manipulation—give left-handed shooters the ergonomic advantage inherent to the AR platform, while also offering all users alternate methods of manipulation to keep things moving smoothly. The drop-in two-stage trigger is tuned for precision work, not competition gaming, giving you a clean break when accuracy counts.

The URX6 handguard is purpose-built: seven sides of M-LOK mounting real estate paired with a continuous Mil-Std 1913 rail on top means you can integrate optics, lights, lasers, and other mission-critical gear without compromise. The handguard resists impact-induced shift, holding zero and accessories right where you mount them. The included 7.62mm open brake tames recoil and is compatible with Knights Armament's QDC Signature Reduction Devices for those running suppressors. The barrel—14.5 inches of cold hammer-forged steel with chrome lining and a 1:10 twist—is built to handle both standard and premium ammunition across the .308 Winchester and 7.62 NATO spectrum.

This is a complete, assembled upper receiver ready to mate with a compatible lower—no gunsmithing required. It's the foundation of a serious rifle build.

Key Features

• High-pressure dual-ejector bolt for reliable function suppressed and unsuppressed
• Fully ambidextrous controls for left-handed and right-handed shooters
• Drop-in two-stage trigger optimized for precision marksmanship
• URX6 handguard with seven M-LOK slots and continuous top rail
• Cold hammer-forged, chrome-lined barrel (14.5-inch, 1:10 twist)
• Integral 7.62mm open brake; compatible with KAC QDC suppressors
• Impact-resistant handguard design maintains zero and accessory placement

Specifications

Frequently Asked Questions

What lower receiver is this upper compatible with?

This is a complete SR-25 K5 upper receiver designed for .308/7.62 NATO AR-pattern lowers. Verify that your lower is chambered for .308 Winchester or 7.62 NATO and built to the AR-10 standard. Always confirm compatibility with your specific lower before assembly.

Can I use a suppressor with this upper?

Yes. The included 7.62mm muzzle brake is compatible with Knights Armament's QDC Signature Reduction Devices. You'll need an appropriate suppressor rated for .308 and the QDC interface, or plan to replace the brake with a compatible muzzle device if running a different suppressor system.

Is this upper assembled and ready to go?

This is a fully assembled upper receiver. Once mated to a compatible lower receiver (which you'll source separately), the rifle is ready for function testing and zeroing. No gunsmithing required on the upper itself.

What's the effective range of the SR-25 K5?

Knights Armament engineered the SR-25 K5 for precision work from close range out to 800 meters. Actual effective range depends on your optics, ammunition, shooter skill, and mission requirements.