Radical Firearms .300 Black Heavy Barreled AR-15 Upper - 12" Rpr Handguard - 16"
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Radical Firearms
Overview
The Radical Firearms .300 Blk Heavy Barreled AR-15 Upper is a complete upper receiver designed specifically for the .300 Blackout caliber, featuring a 12-inch barrel length that strikes a balance between maneuverability and performance. With a 1:8 twist rate, this upper is optimized for stabilizing a variety of bullet weights, while the Melonite barrel coating enhances durability and resistance to wear. This upper commonly appears in builds that utilize a pistol gas system, making it a suitable choice for compact configurations and enhanced control in close-quarters scenarios.
Specifications
Radical Firearms .300 Black Heavy Barreled AR-15 Upper - 12" Rpr Handguard - 16"
Available Merchants
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Build history on GunPartPicker
Builders on GunPartPicker first added the Radical Firearms .300 Black Heavy Barreled AR-15 Upper - 12" Rpr Handguard - 16" to a build in April 2026.
Updated · from real builds on GunPartPicker
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