PRO2A LEFT HAND 22" 5.56 NATO 1/7 Rifle Length NR Side Charging Melonite M-LOK AR-15 Upper

Maximum Ballistic Velocity Paired with Premium Southpaw Ergonomics

Push the 5.56 NATO cartridge to its absolute mechanical limits without standard right-hand compromises. The PRO2A Left Hand 22" 5.56 NATO Rifle-Length Non-Reciprocating (NR) Side Charging Upper Assembly is engineered from the ground up for left-handed marksmen demanding ultimate downrange velocity. By combining a mirrored left-eject port layout with an ergonomic left-side charging handle, this upper keeps hot brass and escaping gases completely out of your line of sight. The non-reciprocating cocking handle stays fully stationary during cycling, preventing it from catching on field gear or optics. Built around an extended 22-inch barrel and tuned with a smooth rifle-length gas system, this premium upper drops natively onto any standard AR-15 lower receiver to construct a highly accurate, soft-recoil precision rifle. Proudly 100% designed, machined, and meticulously hand-assembled in the USA.

Key Features

Mirrored Left-Hand Ejection Port: Specifically designed to safely redirect spent casings and concentrated powder blowback out of the left side, shielding southpaw shooters from facial debris and peripheral distractions.
Stationary Left-Side Charging Lever: Features a non-reciprocating side charger that operates independently from the bolt carrier's movement during live fire. This lets you cycle or clear the chamber while maintaining a locked-in cheek weld and steady target acquisition.
Extended 22-Inch Barrel Velocity: The extra barrel length significantly extends the expansion time of burning powder gases, yielding the highest possible muzzle velocities for the 5.56 cartridge to secure a flatter trajectory and less wind drift at extreme ranges.
Melonite/Nitride Surface Treatment: The premium 4150 CMV steel barrel is fully Melonite treated inside and out. This advanced chemical hardening vastly improves heat dissipation, resists harsh weather corrosion, and maintains crisp rifling integrity over long-term high-volume use.
Fast 1:7 Twist & Rifle-Length Gas: The fast 1:7 twist rate flawlessly stabilizes heavy 69-grain to 77-grain match-grade bullets, while the true rifle-length gas path introduces optimal dwell time to deliver exceptionally soft, flat-shooting cycling.

Technical Specifications

Receiver	Gibbz Arms LEFT HANDED G4 Non Reciprocating Side Charging Billet Aluminum Receiver with Gen 2 Handle, M4 Feed Ramps, Type III Hardcoat Anodized Black
Barrel Length & Material	22 Inch Profile, 4150 Chrome Moly Vanadium Steel, Melonite Treated, Medium Contour
Caliber	5.56 NATO (Fully backward compatible with .223 Remington ammunition)
Twist Rate	1:7 Twist
Gas Operating Block	Rifle-Length System, Low-Profile Gas Block Machined from 4140 Steel, Stainless Steel Gas Tube
Muzzle Device	Standard 1/2-28 Thread Pitch, A2 Birdcage Flash Hider with Crush Washer
Handguard	15" Slim Profile Free-Float M-LOK Rail, Machined from 6061-T6 Aluminum
Manufacturing Origin	100% Made in the USA with Pro2A Tactical Lifetime Factory Warranty

Who Chooses This Upper Receiver?

Left-Handed Long-Range Marksmen

Southpaw precision shooters looking to extract every bit of velocity and long-distance capability from standard 5.56 cartridges select this 22-inch barrel layout to achieve tighter shot groupings and minimize wind deflection past 500 yards.

Southpaw Varmint & Predator Hunters

Hunters who spend long hours behind the glass waiting on varmints choose this setup. The left-side charging configuration cleanly clears large thermal, digital night vision, or oversized scope turrets without scraping knuckles during weapon manipulation.

Suppressed Southpaw Bench Builders

Lefty shooters planning to build a soft-shooting, suppressor-ready rifle choose this configuration. Combining a rifle-length gas block with a dedicated left-eject port directs heavy suppressor blowback gases away from the shooter's breathing zone.