PRO2A Left Hand 20" 6.8 SPC II Rifle Length Melonite M-LOK Upper Receiver

PRO2A Left Hand 20" 6.8 SPC II 1/11 Rifle Length Melonite M-LOK AR-15 Upper

Maximize intermediate downrange energy and eliminate facial gas blowout with the PRO2A Left Hand 20" 6.8 SPC II Rifle Length Melonite M-LOK Upper Receiver. Engineered with 100% American craftsmanship, this premium upper assembly is meticulously purpose-built for southpaw hunters and tactical shooters. Featuring an authentic left-hand ejecting mil-spec forged receiver, it pairs a precision 20-inch 4150 CMV steel barrel with a smooth, soft-shooting rifle-length gas system. Chambered in the powerful 6.8 SPC Spec II configuration with an optimized 1:11 twist rate, this optics-ready upper provides an uncompromised, high-performance foundation for medium-game hunting and precision intermediate-range target builds.

Key Features

True Left-Handed Ejection Port: Engineered from the ground up for left-handed operators, mirroring standard receiver footprints to throw hot spent casings and unburned facial gases cleanly to the left—far away from the shooter’s eyes.
Spec-II Chamber Configuration: Designed with the updated 6.8 SPC Spec II chamber geometry to safely handle increased throat pressures and higher-velocity tactical loadings compared to obsolete, original SAAMI designs.
Full 20" Velocity Maximization: Provides the complete barrel length necessary to burn powder fully, achieving maximum muzzle velocities for the 6.8 SPC cartridge and extending flat downrange trajectories.
Optimized 1:11 Twist Rate: Precision button-rifled with an ideal 1:11 twist configuration engineered specifically to maximize rotational velocity and stability across a wide span of intermediate projectile weights (90gr to 120gr), preventing pressure spikes.
Soft-Shooting Rifle-Length Gas Dwell: Pairing a full-length barrel path with a rifle gas tube layout lowers internal cyclic pressure, yielding a significantly softer recoil impulse and reduced bolt carrier system wear.
Slim Profile Free-Float M-LOK Rail: Machined from high-strength aluminum, the lightweight rail completely isolates the barrel from physical deflection to preserve uniform groupings while providing continuous top rail spacing.

Technical Specifications

Upper Receiver Assembly	Mil-Spec Billet Aluminum, Dedicated Left-Hand Ejection Port Geometry, M4 Feed Ramps, Type III Hardcoat Anodized Black Finish
Barrel Specification	20 Inch Medium Contour, 4150 Chrome Moly Vanadium Steel, Salt Bath Melonite Coated Interior Bore & Exterior Shell
Caliber Configuration	6.8 SPC II
Twist Rate	1:11 Twist
Gas Operating System	Rifle-Length Gas Network, Low-Profile 4140 Steel Gas Block, Seamless Stainless Steel Gas Tube
Muzzle Device Component	Standard A2 Birdcage Flash Hider with Crush Washer Pre-Installed, 5/8x24 Thread Pitch
Handguard Rail	15 Inch Slim Profile Free-Float Aluminum Handguard, Continuous Top Picatinny Alignment, Modular M-LOK Attachment Points
Manufacturing Origin	100% Assembled and Quality Checked in the USA with Pro2A Tactical Lifetime Factory Warranty

Why Buy This Product?

The PRO2A Left Hand 20" 6.8 SPC II Upper Receiver directly eliminates the physical frustration left-handed medium-game hunters encounter when operating a standard rifle platform. Shooting intermediate hunting calibers from right-handed builds forces southpaw operators to breathe in flying sparks, hot gas blowout, and unburned gunpowder, an inconvenience that multiplies when focusing through high-magnification hunting optics. This dedicated left-ejecting platform isolates you from visual disruption, guaranteeing a completely clean, focused line of sight through your glass during critical hunting or target sequences.

From a ballistic performance standpoint, the 6.8 SPC II cartridge shines on a full-length 20-inch barrel path. While carbines limit the powder expansion window, this full length lets you squeeze out every drop of velocity from hard-hitting 110-grain and 120-grain hunting rounds, delivering maximum kinetic impact on targets downrange. Combined with a true 1:11 twist rate to keep internal pressures smooth and a rifle-length gas system to deaden recoil, this assembly ensures your follow-up shots are quick and exceptionally stable. Backed completely by Pro2A Tactical's lifetime factory warranty and built with strictly premium domestic components, this upper assembly transforms your AR setup into an ergonomic hunting machine.

More Information