PRO2A 18" 7.62x39 1/10 Carbine Length Melonite M-LOK AR-15 Upper Kit

Hard-Hitting Ballistic Velocity Meets Reliable AR-15 Component Engineering

Bring the raw, authoritative power of the classic 7.62x39mm cartridge into the modular, highly accurate AR-15 platform. The PRO2A 18" 7.62x39 Carbine-Length Melonite AR-15 Upper Kit is a comprehensive, range-ready master assembly package that includes a precision upper receiver assembly, a premium Mil-Spec bolt carrier group (BCG), an aluminum charging handle, a full lower parts kit, and a 6-position adjustable stock/buffer assembly. Built around an extended 18-inch 4150 CMV steel barrel, this kit maximizes full combustion of 7.62x39mm powder profiles to generate impressive muzzle velocities and flatter trajectories. Every component is specifically tuned to overcome traditional 7.62x39mm AR platform hurdles, featuring an optimized gas port diameter and an enhanced firing pin for reliable ignition of hard steel-case primers. It drops natively onto any standard Mil-Spec AR-15 stripped lower receiver. Proudly 100% designed, machined, and precision-tested in the USA.

Key Features

All-In-One Complete Rifle Build Package: Takes the technical guesswork out of building a specialty caliber AR. This matching configuration ships with a pre-headspaced BCG, lower parts kit, polished trigger assembly, and standard adjustable stock setup to turn a stripped lower into a completed rifle.
Enhanced Ignition & Extraction Engineering: Built specifically to handle surplus ammunition. The included bolt carrier group features an enhanced (extended) firing pin to deliver deep primer strikes on hard steel-cased primers, preventing frustrating failure-to-fire errors.
Maximized 18-Inch Velocity: The extra barrel length unlocks the maximum ballistic performance of the 7.62x39mm round, extending expansion times to deliver hard-hitting energy downrange for hunting and barrier penetration.
Melonite/Nitride Barrel Protection: The heavy-duty 4150 CMV steel barrel is fully treated with an advanced Salt Bath Melonite finish inside and out. This high-grade chemical hardening protects the bore against aggressive gas erosion and environmental elements.
Classic 1:10 Twist Profile: Precision button-rifled with a versatile 1:10 twist rate configuration engineered to perfectly stabilize standard 122-grain and 123-grain projectiles as well as heavy duty tactical options with uniform mechanical consistency.
Slim Profile Free-Float M-LOK Rail: Crafted from premium 6061-T6 aluminum, the free-float rail isolates barrel vibrations to preserve uniform accuracy while providing extensive modular accessory real estate.

Technical Specifications

Upper Receiver	Mil-Spec Forged 7075-T6 Aluminum, M4 Feed Ramps, Type III Hardcoat Anodized Black Finish (Forward Assist & Ejection Port Cover Pre-Installed)
Bolt Carrier Group	Premium Heavy Duty BCG Optimized for 7.62x39mm, Nitride Finish, Enhanced Firing Pin Included, Properly Staked Gas Key
Charging Handle	Standard Mil-Spec Aluminum Charging Handle
Barrel Length & Steel	18 Inch Profile, 4150 Chrome Moly Vanadium Steel, Heavy Contour, Melonite Treated
Caliber	7.62x39mm (Russian)
Twist Rate	1:10 Twist (Optimized to stabilize standard 123gr FMJ, soft point, and hunting projectile profiles)
Gas Operating Block	Carbine-Length System, Custom Enlarged Gas Port, Low-Profile Gas Block Machined from 4140 Steel
Muzzle Device	Standard 5/8-24 Thread Pitch, A2 Flash Hider with Crush Washer Pre-Installed
Handguard	15 Inch Slim Profile Free-Float M-LOK Rail, Full-Length Top Picatinny Rail, Machined from 6061-T6 Aluminum
Lower Parts Kit	Mil-Spec Polished Trigger & Hammer, Standard Pistol Grip, Lower Component Springs, and Pins Included
Stock Assembly	Standard Mil-Spec M4 Stock with 6-position buffer tube, standard 3oz buffer, buffer spring, latch plate, and castle nut
Manufacturing Origin	100% Made in the USA with Pro2A Tactical Lifetime Factory Warranty

Why Choose This Product?

The PRO2A 18" 7.62x39 Carbine Length Upper Kit solves the primary mechanical complications encountered when running this hard-hitting caliber inside an AR platform: light primer strikes, cycling failures, and accelerated barrel wear. While the 7.62x39mm cartridge is celebrated worldwide for its affordable ammunition options and defensive energy, it uses hard primers and fast-burning powders that cause issues in standard, non-optimized AR builds. Pro2A Tactical directly eliminates these failure points by pairing an enhanced, extended firing pin with a custom-drilled gas port designed to cycle both domestic brass and cheap imported steel casing with absolute confidence.