PRO2A 5.5" 40 S&W 1/16 Pistol Caliber NR Side Charging Melonite M-LOK Upper with Flash Can

Dominate close-quarters defense with the ultimate heavy-hitting, ultra-compact platform: the PRO2A 5.5" 40 S&W Non-Reciprocating (NR) Side Charging M-LOK Upper with Flash Can. This premium, 100% American-made complete upper assembly delivers the barrier-penetrating ballistics of the .40 S&W cartridge in a highly maneuverable sub-carbine footprint. Shifting the manual action to a stationary left-side charging handle provides rapid, intuitive manipulation without breaking your sight picture or interfering with low-profile red dots. Equipped with an integrated blast-forward Flash Can tucked neatly inside a modular free-float M-LOK rail, this package forces intense concussive gases directly downrange away from the operator for smooth, comfortable performance.

Key Features

Non-Reciprocating Side Charging Handle: Left-side charging mechanism handle stays completely stationary while firing to shield hands and allow fluid reloads without skinning knuckles on low-mounted red dots.
Blast-Forward Linear Flash Can: Integrated muzzle device redirects sharp concussive reports, noise, and expanding gas straight downrange away from the shooter—essential for short-barreled indoor use.
Ultra-Compact 5.5" Melonite Barrel: Machined from premium 4150 CMV steel and treated with a Salt Bath Melonite finish inside the bore and across the exterior to optimize structural lifespan and resist corrosion.
Versatile 1:16 Twist Rate: Precision button-rifled barrel geometry optimally engineered to stabilize popular 165gr and heavy-grain 180gr standard duty ammunition with consistent close-range accuracy.
Reliable Direct Blowback System: Gas-less operation designed with a ramped, heavy-duty blowback bolt carrier group that delivers consistent feeding, cycling, and extraction out of standard .40 S&W lower receivers (Glock compatible).
Sleek Tucked Handguard Style: A free-float aluminum M-LOK handguard surrounds the base of the flash can, offering a continuous top Picatinny axis and ample room for weapon lights or hand stops.

Technical Specifications

Upper Receiver Assembly	Gibbz Arms G9 Premium Non-Reciprocating Side Charging Billet Upper Receiver, Dedicated Pistol Caliber Slick-Side Profile (No Forward Assist/Dust Cover Needed), Type III Hardcoat Anodized Black Finish
Charging Handle	Left-Side Non-Reciprocating Charging Handle Assembly (Stationary During Firing Cycle)
Barrel	5.5 Inch Profile, 4150 Chrome Moly Vanadium (CMV) Steel, Melonite Treated Interior & Exterior Bore
Caliber	40 S&W (Pistol Caliber)
Twist Rate	1:16 Twist
Operating System	Direct Blowback (No Gas Block or Gas Tube Configuration Required)
Muzzle Device Component	Standard 9/16x24 Thread Pitch, Extended Blast-Forward Linear Flash Can Pre-Installed
Handguard Rail	7 Inch Slim Profile Free-Float Aluminum Handguard, Top Picatinny Alignment, Modular M-LOK Attachment Points (Muzzle Device Tucked)
Manufacturing Origin	100% Assembled, Headspaced, and Quality Checked in the USA with Pro2A Tactical Lifetime Factory Warranty

Why Buy This Product?

Piecing together an ultra-short .40 S&W pistol caliber carbine (PCC) upper frequently leads to harsh gas blowback and severe side muzzle concussion. The PRO2A 5.5" 40 S&W Non-Reciprocating Side Charging Upper with Flash Can directly eliminates these hurdles out of the box. By matching a pre-headspaced, ramped blowback bolt group with a dedicated linear blast director, you gain the compact footprint of a sub-carbine with the comfortable shooting profile of a full-sized firearm. The stationary left-side handle lets you cycle the action instantly without breaking your cheek weld or moving your hand to the back of the receiver. Hand-built and test-fired in the USA, this upper gives you an incredibly reliable, low-recoil option for home defense, vehicle storage, or range use without the premium individual part price tags.