PRO2A 18" 450 Bushmaster 1/24 Mid Length NR Side Charging Melonite M-LOK AR-15 Upper
Extended Velocity and Straight-Wall Power with Premium Side-Cocking Ergonomics
Maximize downrange kinetic energy and unlock the true ballistic velocity of straight-wall hunting ammunition with the PRO2A 18" Non-Reciprocating (NR) Side Charging 450 Bushmaster Upper Receiver Assembly. This 100% American-made complete upper receiver drops directly onto any standard Mil-Spec AR-15 lower receiver to construct an elite big-game rifle system. Shifting the manual action to a stationary left-side charging handle completely clears room under large optics and high-magnification deer hunting scopes. Built around an 18-inch 4150 CMV steel barrel and an optimized mid-length gas block, this assembly ensures ultra-reliable, smooth cycling while squeezing maximum distance from your powder burn.
Key Features:
- Non-Reciprocating Side Charging Handle: The left-side manual handle stays completely stationary while the weapon fires, protecting your support hand and clearing room for scope mounts.
- Extended 18" Barrel Velocity: The extra barrel length increases dwell time and internal powder burn efficiency, giving you flatter trajectories and harder impact signatures at extended ranges.
- Enlarged Ejection Port Cutout: Specially widened receiver port layout ensures effortless clearance of large straight-wall .450 Bushmaster brass, stopping stovepipe failures before they happen.
- Advanced Melonite Barrel Treatment: Fully treated with an advanced Salt Bath Melonite finish inside the bore and across the exterior to extend service life and maximize corrosion resistance against harsh weather.
- Smooth Mid-Length Gas Dynamics: Configured with a mid-length gas operating block to provide softer, highly reliable internal cycling pressures that tame heavy big-bore muzzle recoil.
- Slim Free-Float M-LOK Rail: Machined from high-strength aluminum, the lightweight handguard isolates barrel vibrations to preserve uniform mechanical accuracy while providing a continuous top rail and modular M-LOK slots.
Technical Product Specifications:
| Upper Receiver Assembly | Gibbz Arms G4 Premium Non-Reciprocating Side Charging Billet Upper Receiver, Custom Enlarged Ejection Port, Type III Hardcoat Anodized Black Finish |
|---|---|
| Charging Handle | Left-Side Non-Reciprocating Charging Handle Assembly (Stationary During Firing Cycle) |
| Barrel Component | 18 Inch Profile, 4150 Chrome Moly Vanadium (CMV) Premium Steel, Heavy Contour, Melonite Treated Interior & Exterior Bore |
| Caliber | .450 Bushmaster (Straight-Wall Compliant) |
| Twist Rate | 1:24 Twist |
| Gas Operating Block & System | Mid-Length Gas System, Low-Profile Gas Block Machined from 4140 Steel, Stainless Steel Gas Tube |
| Muzzle Device Component | Standard 5/8x24 Thread Pitch, Big-Bore Muzzle Device with Crush Washer Pre-Installed |
| 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 Choose the PRO2A .450 Bushmaster Side Charging Upper?
Standard rear-charging AR platforms create frustrating bottlenecks when paired with large hunting optics. Trying to clear an extraction issue or cycle a heavy round beneath a low-mounted rifle scope can be slow and awkward. The PRO2A 18" .450 Bushmaster Non-Reciprocating Side Charging Upper directly bypasses this struggle with its fluid, left-side manual cocking mechanism. By combining this premium manual control with an 18-inch 1/24 twist Melonite barrel, you obtain optimal downrange velocities and exceptional sub-MOA precision capabilities without sacrificing the system's reliability. Hand-built and checked for perfect headspacing right here in the USA, this upper gives you target-dropping authority while redefining your heavy-caliber shooting experience.
