PRO2A LEFT HAND 12.5" 300 Blackout 1/8 Pistol Length Melonite M-LOK AR-15 Upper
Product Overview
Engineered specifically for Southpaw operators, the PRO2A Left Hand 12.5" 300 Blackout Pistol Length Melonite M-LOK Upper delivers premium, short-barrel performance without the mechanical compromises facing left-dominant shooters. This fully assembled complete upper receiver brings optimal velocity and duty-grade reliability to the 300 AAC Blackout platform. Built with a robust 12.5-inch 4150 CMV Melonite-treated barrel and a dedicated left-ejecting bolt carrier group, this premium upper is compatible with any standard AR-15 lower receiver configured as a pistol or a registered Short Barreled Rifle (SBR).
Key Features
- True Left-Hand Ejection Port: Mirrored receiver architecture ejects spent casings and harsh blowback gas to the left side, providing a clean, distraction-free sight line for left-dominant shooters.
- Versatile 12.5-Inch Barrel Length: Achieves full powder burn for the 300 Blackout cartridge, securing high velocities while remaining exceptionally agile in tight spaces or vehicular environments.
- Premium Melonite (QPQ Nitride) Finish: The high-grade 4150 CMV barrel features a uniform Melonite layer inside and out, supplying elite defense against bore erosion, extreme heat, and harsh weather.
- Optimized 1:8 Twist Rate: The perfect twist rate calculation engineered to stabilize a broad weight range of 300 BLK ammunition, from light supersonic rounds up to heavy subsonic loads.
- Slim Free-Float M-LOK Handguard: A 10-inch lightweight handguard shrouds the barrel to maximize grip real estate while supporting modular M-LOK mounting systems for lights, lasers, and optics.
Technical Specifications
| Caliber / Chamber | 300 AAC Blackout (300 BLK) |
|---|---|
| Barrel Length | 12.5 Inches |
| Barrel Material | 4150 Chrome Moly Vanadium (CMV) Steel |
| Twist Rate | 1:8 Twist Button Rifled |
| Barrel Finish | Melonite / QPQ Nitride Finish |
| Gas System Length | Pistol-Length Gas System with 0.750" Low Profile Gas Block |
| Upper Receiver | Left-Hand Ejection Forged 7075-T6 Aluminum, M4 Feed Ramps, Type III Hardcoat Anodized |
| Handguard | 10" Premium Slim Free-Float M-LOK Handguard (6061-T6 Aluminum) with Full Top Picatinny Rail |
| Muzzle Thread & Device | 5/8x24 TPI; Standard A2 Flash Hider |
| Manufacturing Origin | 100% Made in the USA |
Why Choose the PRO2A Left-Handed 12.5" 300 Blackout Upper?
The 300 Blackout cartridge is a premier choice for short-barreled tactical weapons, particularly when running suppressed. However, when left-handed shooters use a traditional right-hand ejection port, the excessive backpressure from a suppressor blows toxic carbon and unburnt gas directly into their face. The Pro2A Tactical Left-Hand Upper Receiver Group completely resolves this safety and comfort issue. By mirroring the ejection cycle to the left side and combining it with a duty-grade Melonite barrel and a reliable pistol-length gas system, Pro2A provides a flat-cycling, clean-shooting, American-made upper customized specifically for the Southpaw shooter.
