Knights Armament Sr-15 Ks-3 5.56 Nato 11.5'' Bbl Assembled Upper Rcvr Black

The Knights Armament SR-15 KS-3 5.56 NATO upper receiver pairs a compact 11.5" barrel with the rugged engineering KA is known for, giving you a versatile short-rifle platform that handles like a dream in tight spaces. Built on a cold hammer-forged, chrome-lined barrel with a 1:7" twist rate, this assembled upper is ready to mount on a compatible lower receiver—making it an excellent choice whether you're building your first SR-15 or adding a second upper to an existing KS-1 or KS-2 rifle. The 11.5" barrel length hits that sweet spot between maneuverability and velocity, ideal for shooters who need compact handling without sacrificing 5.56 NATO ballistics.

If you already own an SR-15, you'll appreciate the KS-3's near-complete compatibility across Knights Armament's KS rifle family. Drop this upper onto your existing lower receiver and you've got a new gun without duplicating parts you already have. For those building from scratch, the KS-3 makes a solid foundation for a dedicated short-range rifle, home-defense carbine, or truck gun that doesn't demand space.

The cold hammer-forged barrel and chrome lining are hallmarks of KA's no-nonsense approach to durability. This isn't marketing—it's the kind of barrel material and treatment that stands up to hard use and corrosive environments. The 1:7" twist handles modern 5.56 ammo across the full velocity range, so you're not locked into a narrow ammunition diet.

Key Features

• 11.5" cold hammer-forged, chrome-lined barrel optimized for compact handling
• 1:7" twist rate—stable, reliable, and compatible with standard and modern 5.56 NATO loads
• Nearly 100% compatible with KS-1 and KS-2 rifle systems for existing SR-15 owners
• Assembled upper receiver—ready to install on a compatible lower
• Compact form factor: excellent for transportation, storage, and tactical mobility

Specifications

Frequently Asked Questions

Is the SR-15 KS-3 upper compatible with my existing KS-1 or KS-2 rifle?

Yes. The KS-3 upper features nearly 100% compatibility with other KS-series rifles, making it an ideal secondary upper receiver if you already own a KS-1 or KS-2. Always verify fit with your specific lower before final assembly.

What's included—is this a complete upper receiver?

This is an assembled upper receiver. You will need a compatible lower receiver to complete a functional rifle. The upper receiver itself is ready to install onto a lower.

Why choose an 11.5" barrel?

The 11.5" barrel length offers excellent maneuverability and portability while maintaining effective 5.56 NATO performance. It's compact for transport and storage, and highly efficient for shooters who need a shorter handling profile without sacrificing reliability.

What ammunition does this barrel handle?

The 1:7" twist rate is compatible with standard and modern 5.56 NATO ammunition across the velocity spectrum, giving you broad ammunition compatibility without restriction to specialty loads.