Home > PRODUCTS > UPPERS > 12.7x42 .50 Cal. AR-15 Complete Upper Assemblies
All Big Bore Uppers come complete with:

  • MIL-STD Charging handle
  • Big Bore BCG
  • Big Bore Magazine
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Radical Firearms 10.5" 12.7x42 Complete Upper with 9" MHR Radical Firearms 10.5" 12.7x42 Complete Upper with 9" MHR

  • 10.5" 12.7 x 42 4140V Barrel With Melonite Coating
  • 1 in 20" Twist Rate
  • 49/64 x 20 TPI
  • 12.7 x 42 Chamber
  • Single Feed Ramp
  • .936" Gas Block
  • Stainless carbine-length gas tube
  • Direct Gas Impingement
  • Radical Firearms Panzer Brake
  • Radical Firearms 9" MHR Hybrid Rail System
  • Integrated M-LOK attachment points on the sides and bottom with Picatinny Rails at the fore end for Mounting Lights, Lasers, Bipods & Sights
  • MIL-STD Forged Upper Receiver with RF Dimpled Forward Assist, Shell Deflector
  • Complete 12.7 BCG, Melonite Coated
  • MIL-STD Charging Handle
  • Big Bore Magazine


  • *Does not include dust cover

    MSRP: $589.95
    Radical Firearms 16" 12.7x42 Complete Upper with 15" MHR Radical Firearms 16" 12.7x42 Complete Upper with 15" MHR

  • 16" 12.7 x 42 4140V Barrel With Melonite Coating
  • 1 in 20" Twist Rate
  • 49/64 x 20 TPI
  • 12.7 x 42 Chamber
  • Single Feed Ramp
  • .936" Gas Block
  • Stainless carbine-length gas tube
  • Direct Gas Impingement
  • Radical Firearms Panzer Brake
  • Radical Firearms 15" MHR Hybrid Rail System
  • Integrated M-LOK attachment points on the sides and bottom with Picatinny Rails at the fore end for Mounting Lights, Lasers, Bipods & Sights
  • MIL-STD Forged Upper Receiver with RF Dimpled Forward Assist, Shell Deflector
  • Complete 12.7 BCG, Melonite Coated
  • MIL-STD Charging Handle
  • Big Bore Magazine


  • *Does not include dust cover

    MSRP: $589.95
    10 rd 12.7x42/ 458 SOCOM Magazine 10 rd 12.7x42/ 458 SOCOM Magazine

    • High performance steel magazines.
    • Tested by special military forces and anti-terror units.
    • Fine resistance body coating, enduring up to 96 hours salt-spray test.
    • State-of-the-art anti-tilt self-levelingfollowers in several colors.
    • Improved reinforced floorplate

    MSRP: $40.00