Gorilla Machining GM-15 Stripped Upper Receiver Assembly Kit with Charging Handle, Forward Assist, and Dust Cover GM-URDCFA-1-2
Product Description
When engineering or assembling custom AR-15 rifle configurations, armorers and tactical builders frequently encounter an acute operational bottleneck of structural component procurement lag and part-to-part mismatch errors when sourcing critical upper completion hardware from scattered, non-standardized suppliers. Slight variances in pin hole sizes, spring rates, or component clearances across different brands can introduce unwanted frame-to-hardware loose tolerances, creating issues like sticky forward assist pins or loose dust cover alignment clips. The Gorilla Machining GM-15 Stripped Upper Receiver Combo Kit completely bypasses these stacking tolerance liabilities, packaging a premium, Mil-Spec flat-top upper with an unyielding collection of dimensionally verified completion parts.
The structural core of this versatile assembly is precision-machined from an ultra-dense, 7075-T6 aircraft-grade aluminum alloy forging, yielding massive shear resistance and an exceptional lifespan under heavy reciprocal gas pressures. Following rigorous CNC-turning sequences to fulfill exact military dimensions, the chassis is treated with a non-reflective, Mil-Spec Type III, Class 2 hardcoat black anodized finish to guard against scratching, deep abrasion, and environmental moisture. To minimize cyclic friction and combat carbon baked buildup across intensive firing strings, the interior cylinder bore pathway features a factory-baked application of dry film lubricant, ensuring seamless bolt carrier group tracking velocities.
Executing an optimized, direct-interfacing installation geometry, this upper incorporates pre-cut M4-style feedramps calibrated to blend flawlessly with standard M4 barrel extensions, entirely overriding cartridge nose-diving or feeding stutter. The top face is crowned with a continuous MIL-STD 1913 Picatinny rail field that accommodates tactical optics and iron sights with zero-drift mounting stability under active live-fire vibrations. Arriving in a clean, unassembled format to allow custom tuning, the kit ships fully equipped with a robust mil-spec charging handle, a forward assist assembly outfitted with a heat-treated tool steel pawl, and a complete spring-loaded ejection port dust door array to protect your rifle action from extreme field dirt and debris.
Each individual factory retail bundle contains one Gorilla Machining GM-15 black anodized stripped upper receiver, one mil-spec aluminum charging handle, one forward assist assembly with roll pin and spring, and one complete ejection port cover assembly.
*Administrative Armorer Staging, Upper Assembly Guidance: This comprehensive standard-frame component group (Part # GM-URDCFA-1-2) is strictly dimensioned for standard AR-15 lower receivers and is highly optimized to run intermediate centerfire calibers like 5.56x45mm NATO, .223 Remington, .300 AAC Blackout, 6.5 Grendel, and 7.62x39mm. Armorers must note that this kit is delivered in an unassembled, loose component staging layout, requiring standard bench blocks, a roll-pin punch set, and pivot-pin detailing tools to fully complete the hardware integration tracks. During workbench assembly loops, ensure the dust cover spring is wound under adequate reverse tension before seating the retaining rod, and verify that the forward assist roll pin is driven flush to prevent manual interference with charging handle travel. Always apply a drop of synthetic machine oil to the charging handle operational tracks during final staging to preserve the internal dry-film lube boundaries.
Key Features
- 7075-T6 Forged Armor Base: CNC-machined from dense, high-tensile forged aluminum to guarantee absolute structural integrity and defy high-velocity reciprocal stress.
- Comprehensive Completion Hardware Pack: Bundles a standard mil-spec charging handle, steel-pawl forward assist, and spring-loaded port cover to streamline your workbench build sequence.
- Mil-Spec Type III Anodized Finishing: Coated with a rugged, matte black electrochemical shell that actively repels skin acidity, holster wear, and aggressive cleaning solvents.
- Dry Film Lubricated Bore: The interior tracking chamber features a factory-applied dry-film lube coating to facilitate frictionless bolt carrier group travel and minimize internal scaling.
- Precision M4 Feedramp Matching: Machined with clean, factory-profiled feedramps designed to blend seamlessly with barrel extensions for smooth round presentation.
- Slick Unmarked Picatinny Rail: Crowned with a continuous flat-top 1913 rail field without oversized brand graphics, providing a clean appearance for a customized weapon platform.
Product Specifications
- Brand: Gorilla Machining
- Product Line: GM-15 Series Core Components
- MPN/SKU: GM-URDCFA-1-2
- UPC Barcode: N/A (Manufacturer Direct Core Component SKU)
- Chassis Metallurgy: Precision CNC-Machined Forged 7075-T6 Aluminum / Heat-Treated Tool Steel Elements
- Coating Finishing: Mil-A-8625F Type III Class 2 Hardcoat Anodized Surface Shell / Internal Dry Film Lube Coating
- Operational Dimensions: Standard AR-15 Form Factor / Pre-Cut M4 Style Feedramps / MIL-STD 1913 Optics Interface
- Packing Metrics: 1 Stripped Upper Receiver Group Bundled with Loose Completion Hardware Components Safely in Protective Factory Packaging
