PRO2A 16" 6mm ARC Mid Length Melonite M-LOK AR-15 Upper Receiver | Pro2A Tactical

PRO2A 16" 6mm ARC 1/7.5 Mid Length Melonite M-LOK AR-15 Upper Receiver

Product Overview

The PRO2A 16" 6mm ARC 1/7.5 Mid Length Melonite M-LOK AR-15 Upper Receiver delivers tack-driving precision and match-grade consistency in a high-performance, drop-in barreled upper assembly. Purpose-built to maximize the long-range capabilities of the cutting-edge 6mm Advanced Rifle Cartridge (ARC), this optics-ready upper brings low-recoil, high-velocity terminal ballistics directly to any standard mil-spec AR-15 lower receiver. Engineered around a premium 16-inch 4150 CMV heavy-profile barrel and a free-floating aluminum rail, the system arrives meticulously timed, aligned, and ready to pin onto your lower structure for immediate range deployment.

Key Features

Drop-In Precision Upgrade: Instantly expands your tactical platform capabilities by pinning this pre-assembled, optics-ready barreled upper directly onto any standard mil-spec AR-15 lower receiver.
Precision 1/7.5 Twist Profile: Explicitly lands-and-grooves engineered to perfectly stabilize high-coefficient heavy target bullets cleanly for incredibly flat flight trajectories downrange.
Mid-Length Gas Operating Loop: Optimized cyclic gas timing system combined with a 0.750" low-profile gas block cushions harsh action impulses, dramatically softening recoil and accelerating dot-sight target recovery.
Inside-Out QPQ Melonite Shielding: High-performance liquid salt-bath nitride surface treatment seals internal bore land lines from throat erosion while providing absolute resistance against wet environmental corrosion.
Slim Free-Float M-LOK Rail: Isolates structural barrel harmonic variables to ensure uniform shot-to-shot groupings while establishing a continuous top Picatinny rail plane and modular M-LOK side slots.

Technical Specifications

Receiver	Mil-Spec Forged 7075-T6 Aluminum, Precision Machined M4 Feed Ramps, Type III Hardcoat Anodized Matte Black, Forward Assist & Dust Cover
Barrel Length & Contour	16 Inches; Medium Contour Profile Axis
Barrel Material Composition	4150 Chrome Moly Vanadium (CMV) Steel
Twist Rate	1:7.5 Twist (Optimized for heavy match-grade long-range bullet vectors)
Barrel Coating Treatment	QPQ Melonite / Liquid Salt Bath Nitride Interior Bore and Exterior Shielding for Corrosive Resistance
Gas Impingement Setup	Mid-Length Gas System with 0.750" Low Profile Gas Block, Stainless Steel Gas Tube
Muzzle Thread & Device	5/8x24 TPI (Thread Pitch Layout); Equipped with Standard A2 Style Flash Hider
Handguard Rail Profile	12 Inch Slim Profile Free-Float Aluminum Handguard, Continuous Top Picatinny Rail Alignment, Modular M-LOK Mounting Real Estate
Manufacturing Origin	100% Proudly Assembled, Aligned, and Quality Inspected in the USA with Pro2A Tactical Lifetime Factory Warranty

Why Choose the PRO2A 6mm ARC Free-Float Upper?

Unlocking the true surgical precision of the 6mm Advanced Rifle Cartridge demands strict mechanical harmony and tight tolerance assembly that standard mass-market components cannot match. Pro2A Tactical isolates structural variables on the assembly bench to eliminate tolerance stacking entirely. Our premium 4150 CMV heavy barrels are button-rifled at a tight 1/7.5 twist to ensure heavy match payloads track with razor-sharp sub-MOA groupings. By timing a smooth-cycling mid-length gas loop perfectly inside a rugged free-floated handguard assembly, this barreled upper eliminates external barrel distortion and severe cyclic gas shock. Skip the technical assembly tools and upgrade your platform with a duty-ready precision asset you can trust right out of the box.

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