PRO2A 20" 5.56 NATO 1/7 Rifle Length Melonite 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 AR-15 Upper Kit. This master build package provides a meticulously headspaced 20-inch barrel assembly paired with a smooth-cycling rifle gas system. Engineered as an all-in-one build solution, this kit comes fully populated with a premium M16 profile bolt carrier group, an enhanced charging handle, a complete mil-spec lower parts kit, and a full carbine stock assembly—supplying every essential internal 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, charging handle, full lower parts kit, and rear receiver stock assembly.
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)
Barrel Length / Steel	20 Inches / 4150 Chrome Moly Vanadium (CMV) Steel
Barrel Finish & Profile	QPQ Melonite / Black Nitride (Internal & External) — Heavy Target Profile
Twist Rate	1:7 Twist
Gas System Mechanics	Rifle Length Direct Impingement with a 0.750" Low-Profile Steel Gas Block
Upper Receiver	Milspec 7075-T6 Forged Aluminum, M4 Feed Ramps, Type III Hardcoat Anodized, Forward Assist & Dust Cover
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
Charging Handle	Standard AR-15 Charging Handle
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 Carbine 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 Kit removes the complexity of sourcing structural components across separate vendors by providing a perfectly headspaced and balanced ecosystem out of the box. By coupling an extended 20-inch Tactical Kinetics precision barrel with an advanced M16 Nitride bolt group, an ambidextrous charging handle, a clean single-stage trigger group, and complete stock hardware, this system ensures total hardware harmony. Built entirely in America with strict technical tolerances and guarded by a comprehensive Lifetime Warranty, it offers an elite, high-velocity modern sporting platform setup optimized for raw accuracy and smooth operational durability.