PRO2A 16" 45 ACP 1/16 Pistol Caliber NR Side Charging Melonite Upper

Hard-Hitting .45 Caliber Power Coupled with Stationary Side Cocking Ergonomics

Transform your standard rifle lower receiver or dedicated pistol caliber build into a hard-hitting AR-45 platform. The PRO2A 16" 45 ACP Pistol Caliber Non-Reciprocating (NR) Side Charging Upper Assembly updates traditional manual controls by replacing the standard rear dual-latch pull tab with a left-side charging lever. The handle stays fully stationary while firing, providing a seamless operating zone free from moving external components near your optics or mounting systems. Built around a compliance-friendly 16-inch barrel and engineered for a robust, gas-block-free direct blowback operating system, this complete upper drops natively onto dedicated AR-45 lower receivers or standard multi-cal lowers using 45 ACP magazine conversion blocks. Proudly 100% designed, machined, and precision-assembled in the USA.

Key Features

Stationary Side-Charging Interface: The premium non-reciprocating left-side manual handle operates completely independently from the bolt carrier cycle. This allows for fluid charging from prone or benched layouts and completely seals off the rear opening to block high-pressure blowback gases and unburnt powder from venting into your face.
Proven .45 ACP Ballistic Power: Brings the authoritative downrange impact of the classic .45 Auto handgun round into a highly stable carbine platform, picking up increased muzzle velocity over short handgun layouts while keeping mechanical recoil smooth and predictable.
Melonite/Nitride Barrel Protection: The heavy-duty 4150 CMV steel barrel is fully Nitride/Melonite treated inside and out. This premium chemical hardening vastly extends barrel life, aids in uniform thermal dissipation, and counters harsh weather corrosion.
Optimized 1:16 Twist Rifling: Specifically button-rifled with a versatile 1:16 twist profile to maximize rotation on standard 230-grain FMJ and heavy defensive hollow-point .45 caliber projectiles, ensuring consistent downrange stabilization.
Slim Profile Free-Float M-LOK Rail: Built from durable 6061-T6 aluminum, the free-float handguard completely isolates barrel vibrations to preserve uniform mechanical accuracy while offering extensive M-LOK attachment slots and a top Picatinny rail.

Technical Specifications

Upper Receiver	Gibbz Arms G9 Non Reciprocating Side Charging Billet Aluminum with Gen 2 Handle, Type III Hardcoat Anodized Black
Barrel Length & Steel	16 Inch Profile, 4150 Chrome Moly Vanadium Steel
Caliber	45 ACP
Twist Rate	1:16 Twist
Gas / Operating System	Solid Direct Blowback Operating System (No Gas Tube or Gas Block Needed)
Muzzle Device	45 ACP 5/8-24 threads, Pre-Installed A2 Flash Hider with Crush Washer
Handguard Structure	12" Slim Profile Competition Top 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?

No-NFA Pistol Caliber Carbine Builders

Shooters wanting the heavy impact of a .45-caliber platform but want to completely avoid NFA tax stamps, stabilizing brace legalities, or registration paperwork choose this standard 16-inch rifle-compliant upper receiver setup.

Oversized Optics & Thermal Night Hunters

Hog and predator hunters running bulky low-power variable optics (LPVOs) or wide thermal sights prefer side-charging platforms. The left-side handle clears the wide undersides of scope mounts, protecting hands from scrape damage.

Pistol & Carbine Logistics Unifiers

Enthusiasts who already run a .45 ACP handgun for self-defense select this upper to unify their ammunition requirements, allowing them to carry one class of common ammunition into the field or range lane to feed both firearms.