Product Description

Optimize your custom configuration with the premium PRO2A 13.7" 5.56 NATO Mid-Length Non-Reciprocating (NR) Side Charging Assembled Upper Receiver. Built as a standalone barreled upper assembly, this unit features a 13.7-inch precision barrel paired with an optimized mid-length direct impingement gas system to deliver a smooth cycling impulse and diminished port pressures. The architecture centers around the specialized Gibbz Arms G4 billet receiver layout, providing unhindered left-side manual cycling manipulation.

Key Features

• Non-Reciprocating Left-Side Charger: Premium patent-pending Gibbz Arms G4 billet receiver architecture ensures the side-charging handle remains completely stationary while firing to maintain unobstructed visual clearance under oversized optics.
• Ideal 13.7" Ballistic Length: Offers a compact, agile profile that serves as an excellent baseline configuration for a pin-and-weld muzzle setup to achieve a non-NFA 16-inch structural requirement, or as a high-velocity SBR baseline.
• Refined Mid-Length Gas Dynamics: Softens the overall recoil impulse and dramatically slows component wear compared to over-gassed carbine setups by optimizing pressure dwell time.
• QPQ Melonite Hardened Protection: Inside barrel bore, chamber throat, and exterior walls are fully liquid nitrocarburized to maximize surface hardness, improve thermal dissipation, and resist extreme environmental degradation.
• Modular Free-Float Workspace: A continuous top Picatinny rail aligns flawlessly with a 12-inch lightweight slimline M-LOK handguard for secure accessory attachment without warping barrel zero.

Technical Specifications

Why Choose This Product?

The PRO2A 13.7" 5.56 NATO Non-Reciprocating Side Charging Upper Receiver provides an exceptional, high-tier baseline configuration without forcing you to purchase redundant internal bolt assemblies or standard mil-spec lower components you may already own. Traditional rear-charging upper units create awkward physical manipulation clearances when running high-magnification scopes or bulky night-vision/thermal equipment. Utilizing the premium Gibbz Arms G4 side-charging framework resolves this obstacle entirely, allowing clean manual charging execution while keeping your cheek weld firmly established. Built in America to exacting manufacturing tolerances and guarded by an unconditional Structural Lifetime Warranty, it stands out as a highly reliable choice for shooters demanding customized mechanical durability from an agile platform.