10.5″ 300 Blackout AR-15 Upper Receiver with SHD Quad Rail
Built for shooters who want maximum versatility in a compact package, this 10.5″ 300 Blackout upper combines premium assembly standards with our rugged SHD (Super Heavy Duty) Quad Rail system featuring the patented ASAL anti-slip / anti-lift retention design.
Whether you’re building a suppressed home defense setup, compact truck gun, range rifle, or hard-use tactical platform, the 300 Blackout cartridge excels in short barrels and performs exceptionally well with suppressors.
Manufactured and assembled in the USA with proper torque specs, QC procedures, and attention to detail throughout the build process.
SHD Quad Rail with ASAL Locking System
The SHD Quad Rail utilizes the patented ASAL wedge lock retention system combined with anti-rotation tabs for an exceptionally rigid and secure handguard interface.
Unlike standard clamp-on rails that can loosen or shift under hard use, the ASAL system mechanically locks the handguard to the barrel nut to reduce movement, maintain alignment, and provide a rock-solid feel.
SHD Rail Features:
- Patented ASAL anti-slip / anti-lift retention system
- Wedge lock handguard design
- Anti-rotation tabs
- Full-length Picatinny top rail
- Heavy-duty quad rail construction
- Extremely rigid lockup
- Designed for demanding use and accessory mounting
Ideal for:
- Suppressor setups
- Weapon lights
- IR lasers
- Vertical grips
- Defensive/tactical rifle builds
Why 300 Blackout Excels in a 10.5″ Barrel
300 Blackout was specifically designed to perform efficiently in shorter barrel lengths, making the 10.5″ platform one of the most balanced and proven configurations available.
Unlike some rifle calibers that lose significant performance in compact barrels, 300 Blackout burns powder efficiently in shorter systems and maintains excellent reliability and ballistic performance.
Advantages of 300 Blackout:
- Excellent short-barrel performance
- Optimized for compact AR platforms
- Outstanding suppressor compatibility
- Reliable cycling with subsonic and supersonic ammunition
- Increased energy from shorter barrels compared to 5.56
- Reduced concussion compared to many short 5.56 setups
The pistol-length gas system paired with the 10.5″ barrel helps provide reliable function and smooth cycling, especially in suppressed applications.
Suppressor Ready Configuration
This upper is built with suppressor use in mind.
The 300 Blackout cartridge has become one of the most popular suppressor hosts in the AR platform because of its ability to run both:
- Supersonic ammunition for defensive and hunting applications
- Subsonic ammunition for quieter suppressed shooting
Suppressor-Ready Features:
- 5/8×24 muzzle threads
- 10.5″ barrel optimized for compact setups
- Pistol-length gas system
- Excellent compatibility with subsonic ammunition
- Reduced muzzle blast compared to short-barrel 5.56 rifles
Whether you’re running a dedicated suppressor setup or planning future upgrades, this upper is designed to work exceptionally well in suppressed configurations.
Barrel & Upper Features
Barrel Specifications
- 10.5″ 300 Blackout chamber
- 1:8 twist rate
- 4150 Chrome Moly Vanadium steel
- Contour profile barrel
- Pistol-length gas system
- M4 feed ramps
- 5/8×24 muzzle threads
- A2-style flash hider installed
Upper Receiver Specifications
- 7075-T6 forged aluminum upper receiver
- Type III hard coat anodized black finish
- Mil-spec dimensions
- M4 feed ramps
- Forward assist installed
- Dust cover installed
Gas System
- Low-profile steel gas block
- Stainless steel pistol gas tube
Built & QC Checked in the USA
Every upper is properly assembled, torqued, and quality checked before shipment.
If you select the optional bolt carrier group upgrade, your upper is test fired with that exact BCG to help ensure reliable out-of-the-box function.
Each upper is assembled with attention to detail and built to order — not mass assembled in bulk.
Customize Your Build
Add components directly from the product options menu:
- Bolt Carrier Group
- Charging Handle
- Additional upgrades and accessories
Browse more:
Important NFA Notice
This upper receiver assembly is intended for use on:
- AR pistols
- Registered SBR lowers
- Other lawful firearm configurations
Users are responsible for complying with all applicable federal, state, and local laws.
-300x300.png "15' Gen1 Free Float Quad Rail, photo")
sound of freedom – This was a great set up. I loved being able to customize the set up. Only issue I had was my own fault as a newb to building these. I used a heavy barrel in a slim hand guard. It makes adding attachments tough with clearances. Hoping someday to also get an AR10 from here.