Knights Armament 5.56MM SR-15 KS-3 11.5" Upper Receiver Kit - 121437
Out of stock
Elevate your AR-15 build with the premium Knights Armament 5.56MM SR-15 KS-3 11.5″ Upper Receiver Kit, engineered for unmatched reliability and precision in demanding tactical scenarios. As a cornerstone of Knight’s Armament’s legendary SR-15 platform, this upper receiver kit delivers superior performance, blending innovative design with battle-proven durability to ensure your rifle operates flawlessly round after round.
Key Features
- Chrome-Lined Cold Hammer-Forged Barrel: The 11.5-inch 5.56mm barrel provides exceptional accuracy and longevity, with a 1:7 twist rate optimized for heavier bullets, ideal for close-quarters engagements.
- URX 4 M-LOK Handguard: Lightweight and modular, this free-float rail system offers ample space for accessories while maintaining a low-profile design that enhances handling and reduces weight.
- E3 Enhanced Bolt Carrier Group: Featuring enlarged ejection port and multi-lobe cam pin, this bolt extends service life up to 20,000 rounds, minimizing malfunctions and downtime during extended use.
- Mod 2 Gas System: A sealed and adjustable piston-like reliability in a direct impingement setup, reducing gas blowback and ensuring smoother cycling for consistent performance.
- M4 Feed Ramps and T-Marked Upper: Facilitates reliable feeding and easy barrel installation, compatible with a wide range of magazines and ammunition types.
Specifications
- Caliber: 5.56mm NATO
- Barrel Length: 11.5 inches
- Receiver Material: 7075-T6 Aluminum, Anodized Black Finish
- Forward Assist: Factory Installed
- Port Door / Dust Cover: Factory Installed
- Weight: 60.8 oz
- Overall Length: 20 inches
- Width / Height: 2.25 inches
Why Choose This Product
Built to address common challenges in tactical firearms, the SR-15 KS-3 Upper Receiver Kit solves issues like unreliable cycling and excessive recoil found in standard AR-15 uppers. Its advanced E3 bolt and Mod 2 gas system provide enhanced reliability in adverse conditions, while the lightweight construction improves maneuverability without sacrificing strength. Perfect for professionals and enthusiasts seeking a high-end upgrade that boosts accuracy, reduces maintenance, and delivers the confidence needed for critical applications. This kit integrates seamlessly with mil-spec AR-15 lowers, making customization straightforward and effective.
Don’t settle for ordinary—invest in the Knights Armament SR-15 KS-3 11.5″ Upper Receiver Kit today and experience the pinnacle of AR-15 engineering. Upgrade your setup for superior tactical performance and reliability that stands the test of time.
Frequently Asked Questions
1. Is the Knights Armament SR-15 KS-3 Upper compatible with standard AR-15 lowers?
Yes, this upper receiver kit is designed to mil-spec standards and mates perfectly with any standard AR-15 lower receiver, ensuring a reliable and secure fit for your build.
2. What makes the E3 bolt carrier group special?
The E3 BCG features an improved extractor and ejector design that enhances reliability and extends the bolt’s lifespan to approximately 20,000 rounds, reducing the need for frequent replacements.
3. Does the kit include the charging handle and bolt carrier group?
This upper receiver kit includes the complete assembly with the E3 bolt carrier group and charging handle, ready for immediate installation on your lower receiver.
| Weight | 60.8 oz |
|---|---|
| Dimensions | 20 × 2.25 × 2.25 in |
| Finish | Anodized, Black |
| Forward Assist | Factory Installed |
| Port Door / Dust Cover | Factory Installed |
| Receiver Material | 7075 Aluminum |
| T-Marks | T-Marked |
| Feed Ramps | M4 |
| MPN | 121437 |
| UPC | 819064019435 |
Compliance
NFA (National Firearms Act) compliance is crucial for legal ownership and transfer of regulated firearms and accessories like short-barreled rifles, suppressors, and certain types of ammunition, ensuring adherence to federal regulations to avoid legal penalties and ensure responsible firearm ownership.
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