PRO2A Left Hand 18" 5.56 NATO 1/8 Mid Length Melonite Upper | Pro2A Tactical

PRO2A LEFT HAND 18" 5.56 NATO 1/8 Mid Length Melonite M-LOK AR-15 Upper

Full-Length Velocity Meets True Left-Handed Ejection Performance

Maximize muzzle velocity and downrange ballistics from the 5.56 NATO cartridge without dealing with face-directed gas blast or casing deflection. The PRO2A Left Hand 18" 5.56 NATO Mid-Length Melonite M-LOK AR-15 Upper introduces true layout equity to Southpaw shooters. By mirroring the physical ejection path to the left side, this assembly routes blinding gases, unburnt powder residue, and spent brass completely away from your face. Built around an extended 18-inch 4150 CMV steel barrel, this configuration utilizes a smooth mid-length gas system to balance internal carrier velocities and decrease system stress. It arrives complete as a pre-assembled top-end ready to drop natively onto any standard Mil-Spec AR-15 lower receiver. Proudly 100% designed, machined, and precision-tested in the USA.

Key Features

Dedicated Left-Handed Ejection Port: Engineered with a mirrored receiver profile that cleanly throws hot brass and powder blowback to the left side, shielding a left-dominant shooter's eyes and face.
Maximized 18-Inch Bore Velocity: The extended 18-inch barrel length provides full powder combustion for increased muzzle velocity and optimized downrange kinetic energy, perfect for long-range target work or predator hunting.
Softer Mid-Length Gas Profile: Swapping shorter gas designs out for a true mid-length gas tube scales back intense extraction pressures, decreasing mechanical component wear while establishing an exceptionally soft recoil impulse.
Melonite/Nitride Barrel Protection: The heavy-duty 4150 CMV steel barrel undergoes an advanced Salt Bath Melonite process inside and out. This high-grade treatment increases surface slickness, shrugs off moisture, and fights off gas port erosion.
Versatile 1:8 Twist Rate Profile: Precision button-rifled with a clean 1:8 twist configuration engineered to perfectly stabilize standard 55-grain target loads up to heavy duty tactical 77-grain match choices with uniform mechanical consistency.
Slim Profile Free-Float M-LOK Handguard: Crafted from aircraft-grade 6061-T6 aluminum, the free-float rail isolates barrel vibrations to preserve uniform mechanical accuracy while providing extensive modular M-LOK accessory attachment space.

Technical Specifications

Upper Receiver	Dedicated Left-Handed Ejection, Mil-Spec Billet Aluminum, M4 Feed Ramps, Type III Hardcoat Anodized Black Finish
Barrel Length & Steel	18 Inch Profile, 4150 Chrome Moly Vanadium Steel, Heavy/Medium Contour, Melonite Treated
Caliber	5.56 NATO (Fully compatible with .223 Remington ammunition)
Twist Rate	1:8 Twist (Optimized to stabilize a massive profile array of light-to-heavy 55gr, 62gr, and 77gr projectiles)
Gas Operating Block	Mid-Length System, Low-Profile Gas Block Machined from 4140 Steel, Stainless Steel Gas Tube
Muzzle Device	Standard 1/2-28 Thread Pitch, A2 Flash Hider with Crush Washer Pre-Installed
Handguard Structure	15 Inch Slim Profile Free-Float M-LOK Rail, Full-Length Top Picatinny Rail, Machined from 6061-T6 Aluminum
Manufacturing Origin	100% Made in the USA with Pro2A Tactical Lifetime Factory Warranty

Why Choose This Product?

The PRO2A Left Hand 18" 5.56 NATO Mid Length Upper Receiver directly eliminates the operational frustrations left-dominant shooters encounter on standard right-handed rifles: face-directed gas blowback, mirror-image handling gymnastics, and compact tracking failure. Traditional right-handed configurations dump unburnt powder residue and toxic gases directly across a Southpaw shooter's face—a painful issue that grows worse when firing long hunting strings or running a suppressor. Shifting the physical shell gate permanently solves this problem, ensuring clear vision and pure lung comfort.

Furthermore, picking an 18-inch barrel configuration lets you harvest full velocity potential from a lightweight semi-automatic platform, stretching the legs of your rifle past normal distances without entering restrictive NFA registration fields. Paired with a smooth mid-length gas operating block, it limits high bolt cycling speeds to maximize parts longevity and soften muzzle snap. Backed completely by Pro2A Tactical's signature Lifetime Factory Warranty and machined with 100% American craftsmanship, this upper delivers dedicated ergonomics and legal confidence right out of the box.

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