PRO2A 20" 5.56 NATO 1/7 Rifle Length NR Side Charging Melonite M-LOK AR-15 Upper Kit

Product Description

Maximize the full ballistic performance, maximum muzzle velocity, and long-range accuracy of the 5.56x45mm cartridge with the complete PRO2A 20" 5.56 NATO Rifle-Length Non-Reciprocating (NR) Side Charging AR-15 Upper Kit. This master build package provides a meticulously headspaced 20-inch barrel assembly paired with a smooth-cycling rifle gas system and a Gibbz Arms G4 billet side-charging receiver. Engineered as an all-in-one build solution, this kit comes fully populated with a premium M16 profile bolt carrier group, an integrated non-reciprocating charging handle assembly, a complete mil-spec lower parts kit, and a full carbine stock assembly—supplying every essential component required to complete your stripped lower receiver.

Key Features

All-Inclusive Master Build Kit: Bundles the complete barreled upper receiver with a premium bolt carrier group, non-reciprocating charging mechanics, full lower parts kit, and rear receiver stock assembly.
Non-Reciprocating Left-Side Charger: The patent-pending Gibbz Arms G4 side-charging handle remains stationary during cycling, preventing standard rear charging handle interference under large long-range optics.
Optimized Velocity Profile: 20-inch heavy-duty barrel profile ensures full powder burn to capture maximum velocity, flat trajectories, and true match-grade terminal performance.
Ultra-Smooth Rifle Recoil: True rifle-length direct impingement gas dynamics drop peak port pressures significantly, delivering clean cycling and an incredibly soft recoil impulse.
QPQ Melonite Extreme Armor: Barrel bore, chamber, and exterior are fully liquid nitrocarburized to exceed mil-spec chrome lining in surface hardness, heat dissipation, and corrosion resistance.
Slim Profile M-LOK Workspace: Features a continuous top Picatinny rail interface seamlessly blended into a 15-inch free-floating M-LOK handguard for rigid mounting stability.

Technical Specifications

Caliber / Chambering	5.56 NATO (Fully compatible with .223 Remington)
Upper Receiver Housing	Gibbz Arms G4 Non-Reciprocating Side Charging, Billet Aluminum, Type III Anodized
Charging System	Left-Side Non-Reciprocating Handle Assembly (Gen 2 Handle Included)
Barrel Length / Steel	20 Inches / 4150 Chrome Moly Vanadium (CMV) Steel
Barrel Finish & Profile	QPQ Melonite / Black Nitride (Internal & External) — Medium Profile
Twist Rate / Feed Ramps	1:7 Inches Right-Hand Twist / Precision Machined M4 Feed Ramps
Gas System Mechanics	Rifle Length Direct Impingement with a 0.750" Low-Profile Steel Gas Block
Handguard System	15-Inch Free-Float 6061-T6 Aluminum M-LOK Rail
Muzzle Configuration	Standard A2 Birdcage Flash Hider / 1/2-28 TPI Thread Pitch
Bolt Carrier Group (BCG)	M16 Profile Full-Auto Capable, Case Hardened 8620 Steel Carrier, 9310 Steel Bolt (MPI Tested), Advanced Nitride Finish
Lower Parts Kit (LPK)	Complete AR-15 Lower Parts Kit (Standard Milspec ELG Trigger / Fire Control Group, Pistol Grip, Detents, Springs, Pins, and Safety Selector)
Stock & Buffer Assembly	6-Position Collapsible M4 Stock, Mil-Spec Diameter Buffer Tube, Carbine Recoil Buffer, and High-Tensile Buffer Spring
Manufacturing Origin	100% Designed, Machined, and Assembled in the United States
Warranty Protection	Backed by Pro2A Tactical's Structural Lifetime Warranty

Why Choose This Product?

The PRO2A 20" 5.56 NATO Rifle Length Non-Reciprocating Side Charging Kit removes the complexity of sourcing structural components across separate vendors by providing a perfectly headspaced and balanced ecosystem out of the box. Standard rear charging systems force shooters to compromise on optical eye-relief or wrestle with low-clearance mounts. By employing the specialized Gibbz Arms G4 system, this platform allows fast, unhindered charging mechanics while utilizing an extended 20-inch precision barrel to maximize downrange kinetic energy. Completely paired with an advanced M16 Nitride side-charging bolt group, complete internal frame parts, and stock hardware, this system ensures total hardware harmony under the protection of a full Lifetime Warranty.