PRO2A LEFT HAND 10.5" 12.7x42 (50 Beowulf) 1/20 Carbine Length Melonite NR Side Charging M-LOK AR-15 Upper Kit

Product Overview

The Pro2A Left Hand 10.5" 12.7x42 Carbine Length Upper Kit offers an incredibly compact, hard-hitting package for Pistol or SBR builds tailored exclusively for left-handed shooters. Chambered in 12.7x42mm (fully compatible with .50 Beowulf loads), this complete kit utilizes premium side-charging ergonomics. Delivering massive thump from a short barrel system, it maintains flat-out reliability under high straight-walled cartridge pressures while routing gas and debris away from your face.

Key Features

Maneuverable 10.5" Design: Perfectly optimized for close-quarters platforms, tactical applications, and dense brush tracking where a shorter setup is required.
Dedicated Left-Hand Mirroring: True southpaw engineering routes hot big-bore brass to the left, away from the shooter's line of sight.
Premium Non-Reciprocating Layout: Side charging layout keeps the action handle stationary while cycling, preventing mechanical optics interference.
Enlarged Ejection Porting: Machined specifically to reliably cycle heavy-grain 12.7x42 casings without stovepiping or cycle blockages.

Technical Specifications

Upper Receiver	Patented Gibbz Arms G4 Billet Aluminum Non-Reciprocating Side Charging Upper Receiver, Left Hand Ejection, Enlarged Big Bore Ejection Port, M4 Feed Ramps, Anodized Finish
Charging System	Right-Side Non-Reciprocating Charging System (Static Handle Design) for Left-Eject Configuration
Barrel Length & Profile	10.5-Inch Medium Profile
Caliber	12.7x42mm (.50 Beowulf Compatible)
Twist Rate Matrix	1:20 Twist Rate
Barrel Material & Treatment	4150 Chrome Moly Vanadium Steel, Premium Corrosion-Resistant Melonite Finish
Gas Operating Block	Carbine Length Direct Impingement, Low-Profile Steel Gas Block, Stainless Steel Gas Tube
Muzzle Thread & Device	49/64x20 Thread Pitch, Standard Big-Bore Thread Protector or Flash Hider Option
Handguard Rail	10" Slim Free-Float M-LOK Handguard, Machined from 6061-T6 Aluminum with Top Picatinny Rail
Bolt Carrier Group	Full Auto M16 Profile, Premium Nitride Finish, Heavy Duty Ejector & Extractor Assembly, MPI Tested
Lower Parts Kit	Full Mil-Spec Lower Parts Kit (LPK), Machined from Domestic Heat-Treated Steels (Polished Triggers & Hammer, Springs, Pins, and Grip Components Included)
Stabilizing Assembly	High Density Polymer Pistol Stabilizing Blade , Carbine Buffer Tube, Buffer Spring, and 3oz Buffer, etc.
Manufacturing Origin	100% Made in the USA with Pro2A Tactical Lifetime Factory Warranty

Who Chooses This Upper Receiver?

CQB & Brush Hunting Operators

Southpaw hunters tracking large game or hogs in dense thickets choose this 10.5-inch setup. It yields massive stopping power in a fast-handling pistol or SBR layout without exposing the shooter to facial brass ejection.

Tactical Southpaw Marksmen

Shooters demanding enhanced ergonomic manipulation rely on the stationary side-charging system. It enables instant action manipulation and clearing functions without abandoning your cheek weld or reaching awkwardly over the rear stock.

Custom SBR & Pistol Builders

Custom gunsmiths aiming to construct a dedicated, large-bore AR platform select this matching build kit. It drops directly onto standard mil-spec lowers, transforming compact configurations into heavy-duty 50-caliber utilities.