AT3™ Assembled Pistol Upper for AR-15 - .300BLK - 8.5" Barrel - 7" Free Float Quadrail - No BCG/CH - 3 Colors
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- Free standard shipping on orders $139+ details
- 90-day no-hassle returns policy
- Backed by the AT3 Lifetime Warranty! what it covers
Product description
AT3™ Assembled Pistol Upper for AR-15 – 8.5″ 300 BLK Barrel with 7″ Free Float Quad Rail
Built to Order – Ships Within 3 Business Days
This assembled upper delivers an ultra-compact, hard-hitting platform for AR pistol builds with the proven reliability of quad rail accessory mounting. This is the foundation for shooters building a suppressor host, backpack gun, or the most compact defensive setup where you need maximum stopping power in the smallest package possible. The 8.5-inch barrel is purpose-built for 300 BLK—whether you’re running supersonic loads for hunting and home defense or subsonic rounds with a suppressor for quiet work. The 7-inch Pro Quad Rail gives you four sides of Picatinny rail for rock-solid mounting of lights, lasers, and foregrips without worrying about adapter compatibility.
The KAK OE-SPEC 8.5-inch barrel in 300 BLK pairs with a pistol-length gas system for reliable cycling with both supersonic and subsonic ammunition. The 7-inch Pro Quad Rail provides secure accessory mounting on all four sides while keeping the overall profile compact. The quad rail is lightened down all four sides for weight reduction while remaining solid enough to handle heavy use. Five integrated QD sockets give you multiple sling mounting options for any configuration.
Built on AT3’s slick side billet upper receiver with a low-profile .750 steel gas block and stainless gas tube, this setup is ready to run once you add your choice of bolt carrier group and charging handle. The AT3 birdcage flash hider effectively reduces muzzle flash and gives the muzzle a clean, finished look.
Note: Does not include bolt carrier group or charging handle. The upper is shipped fully assembled.
Features
- 8.5-inch barrel with pistol-length gas system for reliable cycling with supersonic and subsonic loads
- 7-inch Pro Quad Rail with four sides of Picatinny rail for secure accessory mounting
- Lightened rail design reduces weight while maintaining strength
- Five integrated QD sockets for multiple sling configurations
- Slick side billet upper receiver for clean lines
- Low-profile .750 steel gas block and stainless steel gas tube
- Birdcage flash hider reduces muzzle flash
- Available in Black, Flat Dark Earth, and OD Green
Specifications
- Brand: AT3 Tactical
- Model: Assembled Pistol Upper for AR-15 – .300BLK – 8.5″ Barrel – 7″ Free Float Quadrail – No BCG/CH
- MPN: FFQR-P-85-7-BLK-300
- Caliber: 300 BLK
- Barrel Length: 8.5 inches
- Gas System: Pistol-length
- Handguard Length: 7 inches
- Handguard Type: Free-float quad rail
- Handguard Material: 6061-T6 Aluminum
- Handguard Weight: 9 ounces
- Inside Diameter: 1.35 inches
- Upper Receiver: Slick side billet
- Gas Block: .750 low-profile steel
- Muzzle Device: Birdcage flash hider (5/8×24 thread)
- Color Options:
- Black
- Flat Dark Earth – H-267 Cerakote Magpul® Flat Dark Earth
- OD Green – H-232 Cerakote Magpul® OD Green
What’s Included – Installed
- 1x Assembled Upper Receiver
- 1x 7″ AT3 Pro Quad Rail Handguard
- 1x 8.5″ KAK OE-SPEC 300 BLK Barrel
- 1x AT3 Birdcage Flash Hider & Crush Washer
- 1x Pistol-Length Gas Tube
- 1x Low-Profile Gas Block
All 3 options on this page
- AT3™ Assembled Pistol Upper for AR-15 - .300BLK - 8.5" Barrel - 7" Free Float Quadrail - No BCG/CH - 3 Colors - Color: Black | SKU: FFQR-P-85-7-BLK-300
- AT3™ Assembled Pistol Upper for AR-15 - .300BLK - 8.5" Barrel - 7" Free Float Quadrail - No BCG/CH - 3 Colors - Color: Flat Dark Earth | SKU: FFQR-P-85-7-FDE-300
- AT3™ Assembled Pistol Upper for AR-15 - .300BLK - 8.5" Barrel - 7" Free Float Quadrail - No BCG/CH - 3 Colors - Color: OD Green | SKU: FFQR-P-85-7-ODG-300
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Questions & Answers
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Warranty & returns
Backed by the AT3 Lifetime Warranty!
All AT3 Tactical Brand Products carry a lifetime warranty against manufacturer’s defects.
This includes AT3 Red Dot Sights, Handguards, Iron Sights, and any other product that carries the “AT3 Tactical” or “AT3™” name. For other brands (ex. Magpul or Troy), please refer to the manufacturer’s warranty policy.
In the event that your AT3™ product becomes unusable, we will repair or replace the product at no charge to you.
If we cannot repair your product, we will replace it with a product in perfect working order of equal or better physical condition. The warranty is fully transferable, but we may require information about the original purchase to validate the authenticity of the product.
If your product is in need of warranty service, please contact AT3 Tactical to start the process
Our contact info is available here. To expedite processing, please provide your order information and description of the defect.
Please note: The AT3 Lifetime Warranty does not cover loss, theft, intentional damage or cosmetic damage that doesn’t affect the performance of the product.
90-day no-hassle returns
The AT3 Tactical store has a 90 day no-hassle return policy for products in good condition. You can view the full details of our return policy here.
If you encounter an issue or defect with a product after 90 days of your purchase, you can refer to the manufacturer for a warranty claim. Their policies are below.
