PRO2A 7.5" 300 Blackout Pistol Length Melonite AR-15 Upper Kit | Complete Pistol Build Package

PRO2A 7.5" 300 Blackout Pistol Length Melonite AR-15 Upper Kit

Build your ultimate close-quarters personal defense weapon with the PRO2A 7.5" 300 Blackout Pistol Length Melonite M-LOK Upper Kit. This 100% American-made master build bundle contains every critical hardware component required to transform a standard stripped lower receiver into a highly reliable, heavy-hitting AR pistol configuration. Engineered specifically to maximize the ballistic footprint of the 300 AAC Blackout cartridge in short configurations, this optics-ready kit pairs a rugged 4150 CMV steel barrel with a premium forged upper. Crucially, this master bundle ships complete with a matching pre-headspaced bolt carrier group, a full mil-spec lower parts kit (LPK), and a complete pistol buffer tube extension assembly to provide seamless mechanical synergy right out of the box.

Key Features

All-In-One Master Rifle Package: Eliminates technical build guesswork by packaging the upper assembly, a pre-headspaced BCG, a complete lower internal hardware kit, and a matching buffer extension group together.
Tailored 1:7 or Fast 1:5 Twist Choice: Choose between a versatile 1:7 twist for standard supersonic ammunition or opt for the ultra-fast 1:5 rotational twist configuration specifically engineered to flawlessly stabilize heavy subsonic projectiles out of micro-length barrels.
Advanced Melonite Barrel Protection: The heavy-duty 4150 Chrome Moly Vanadium steel barrel is fully treated with an advanced Salt Bath Melonite finish inside the bore and across the exterior to extend operational service life and maximize corrosion resistance.
Reliable Pistol-Length Gas Dynamics: Precision engineered to provide consistent internal cycling pressures across a wide spectrum of grain weights, cleanly cycling fast supersonic defense rounds up to heavy suppressed configurations.
Slim Profile 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 spacing.
Complete Mil-Spec Hardware Package: Outfitted with a complete small parts kit, single-stage polished trigger assembly, an A2 pistol grip, and a dedicated round pistol-spec buffer tube assembly.

Technical Specifications

Upper Receiver Assembly	Mil-Spec Forged 7075-T6 Aluminum, M4 Feed Ramps, Forward Assist & Port Cover, Type III Hardcoat Anodized Black Finish
Bolt Carrier Group	Full M16 Profile, Heavy-Duty 9310 Steel Bolt Face, Nitride/Melonite Treatment, Properly Staked Gas Key, MPI Tested
Charging Handle	Standard Milspec Charging Handle
Barrel	7.5 Inch Profile, 4150 Chrome Moly Vanadium Steel, Medium Contour, Melonite Treated Interior & Exterior Bore
Caliber	300 AAC Blackout (7.62x35mm)
Twist Rate Options	1:7 Twist or 1:5 Twist
Gas Operating Block	Pistol-Length Gas System, Low-Profile Gas Block Machined from 4140 Steel, Stainless Steel Gas Tube
Muzzle Device Component	Standard 5/8x24 Thread Pitch, A2 Flash Hider with Crush Washer Pre-Installed
Handguard Rail	7 Inch Slim Profile Free-Float Aluminum Handguard, Competition Top Picatinny Alignment, Modular M-LOK Attachment Points
Lower Receiver Parts Kit	Complete Mil-Spec Spring and Pin Kit, Polished Single-Stage Hammer and Trigger Assembly, Standard A2 Pistol Grip
Pistol Brace	Standard Blade, AR-15 Pistol Buffer Tube, Standard 3oz Carbine Buffer, and High-Tensile Buffer Spring, Latch Plate, Castle Nut
Manufacturing Origin	100% Assembled and Quality Checked in the USA with Pro2A Tactical Lifetime Factory Warranty

Why Buy This Product?

The PRO2A 7.5" 300 Blackout Pistol Length Melonite Upper Kit directly capitalizes on what makes the 300 BLK cartridge legendary: complete powder burn and peak terminal efficiency inside short configurations. While standard 5.56 NATO cartridges suffer from catastrophic velocity drops and massive muzzle flash profiles when fired out of barrels shorter than 10 inches, the 300 Blackout achieves an optimal velocity burn inside a compact 7.5-to-9-inch barrel path. This translates to heavy-hitting, full-power ballistic expansion out of a highly maneuverable platform that fits effortlessly into vehicular consoles or backpack layouts.

Sourcing parts across separate distributors often introduces variation in manufacturing tolerances, resulting in short-cycling, extraction errors, or critical light primer strikes. Pro2A Tactical systematically addresses this challenge by providing a completely balanced, factory-matched master bundle where the gas port size, buffer weight, and pre-headspaced M16 bolt carrier group are specifically optimized to operate under uniform velocities out of the box. Furthermore, by giving builders an explicitly fast 1:5 twist alternative, you solve the tumbling and keyholing issues commonly encountered when pushing heavy 220-grain subsonic bullets through short, slower-twisting barrels. Safely clearing suppressors and delivering sub-MOA precision, this premium complete conversion package transforms your stripped lower receiver into a rock-solid defense asset.

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