Complete Upper - 13.9" Lightweight with Gas Piston System
These complete uppers have been assembled and test-fired. They are ready to ship and are plug-and-play. Built with a 13.9" lightweight barrel, these uppers emphasize precision accuracy over other brands and feature a dedicated gas piston system by Superlative Arms. The package includes a suppressor-ready Keymo muzzle device and a Gas Buster Warhammer Mod2 charging handle.
Pinned & Welded for Compliance
The Dead Air Keymo muzzle device is pinned and welded to achieve a legal 16" rifle length. Simply attach this upper to your lower receiver and enjoy high performance with reliability at an affordable price.
Custom muzzle devices available upon request.
High-Quality Billet Upper Receiver
Our billet uppers are CNC-machined from 7075-T6 aluminum, featuring a sleek, durable profile. These are designed to handle heavy use and extreme conditions.
Premium Handguard
The upper receiver is paired with a 13" 6061-T6 CNC-machined billet MLOK handguard. This handguard is designed to endure heavy impact without affecting optic alignment. It mates directly to the upper and includes anti-rotational tabs. The steel low-profile barrel nut requires no timing and fits perfectly under the gas system.
Precision-Machined Barrel
The 13.9" barrel is produced from raw bar stock to finished product with strict quality control. It is stress-relieved after rifling, and barrel extensions are torqued after nitride treatment.
Barrel Specifications:
- Manufacturer: PAMAX Tactical Razor Barrel
- Length: 13.9" (Pinned and welded to legal 16")
- Weight: 19.34 oz
- Material: 4150 CroMv Mil-B-11595E
- Caliber: 5.56 NATO
- Profile: M4
- Twist Rate: 1:7
- Thread Pitch: 1/2 x 28
- Gas Block Size: .750
- Gas System: Mid-Length
- Crown: 11-degree
- Finish: Nitride
- Barrel Extension Finish: Nitride
Keymo Muzzle Device
The included Dead Air Keymo suppressor mount is pinned and welded in place, making it suppressor-ready out of the box.
Superlative Arms Gas Piston System
We use the Superlative Arms Gas Piston System, the gold standard for gas flow control on AR platforms, ideal for suppressors. Unlike direct impingement systems, this gas piston design moves the bolt carrier via a rod instead of direct gas, reducing fouling and increasing reliability—especially in suppressed setups. This system maintains minimal weight while offering superior performance.
Warhammer Mod2 Charging Handle
The Warhammer Mod2 charging handle is made from 6061-T6 bar stock and milled to spec. It is fully ambidextrous and features gas-deflection technology to mitigate excess blowback when running suppressed.
Build Overview & Features
- 7075-T6 Billet Matched Upper Receiver
- 6061-T6 Matched Billet MLOK 13" Handguard
- 13.9" Nitride 5.56 NATO Barrel (Compatible with 5.56/.223 ammunition)
- Keymo Muzzle Device (Pinned & Welded)
- Mid-Length Piston Gas System & BCG
- Mil-Spec Forward Assist
- Ambidextrous Gas Buster Warhammer Mod2 Charging Handle
Warranty & Quality Guarantee
All of our parts come with a warranty that we stand behind. These uppers are designed to withstand abuse, offer high-quality USA-made parts, and outperform the competition—all while maintaining an affordable price point.
***Optic, Red Dot, and Mount NOT included.***
