Jefferson Armory | 16″ M4 Carbine Length 5.56 NATO Railed Gas Block Build Kit with MBUS Sights



Original price was: $599.00.Current price is: $539.00.

Handling firearms or firearms parts can expose you to lead and other petroleum products known to the State of California to cause cancer, birth defects, or other reproductive harm. Wash hands thoroughly after handling. For more information go to (CA Health and Safety Code Section 25249.6).

The Jefferson Armory M4 Carbine MBUS Build Kit includes everything you need to build your AR other than the lower receiver. Includes Magpul MBUS Sights.

Build kit does not include magazine.

This Product Includes:

  • Upper Receiver Assembly
  • Lower Parts Kit
  • Buffer Tube Assembly (With 6 position adjustable stock)
  • M4 Furniture

        Product Details

Upper Receiver Assembly:

  • Caliber: 5.56 NATO
  • Barrel Length: 16″
  • Barrel Material: 4150 CMV
  • Barrel Profile: M4
  • Barrel Feed Ramps: M4
  • Twist Rate: 1-7 Twist
  • Barrel Finish: Black Nitride
  • Gas System: Carbine
  • Gas Block Type: Railed
  • Gas Block Diameter: .750″
  • Muzzle Device: A2 Flash Hider
  • Muzzle Thread: 1/2-28
  • Handguard: M4 Style Handguard
  • Upper Receiver: Forged 7075 T6 Aluminum
  • Upper Receiver Type: M4
  • BCG: M16 – Full Auto
  • BCG Finish: Black Nitride
  • Charging Handle: Mil-Spec

Lower Parts Kit

  • AR-15 Fire Control Group
  • Safety Selector Assembly
  • Bolt Catch Assembly
  • Magazine Catch Assembly
  • Front & Rear Takedown/Pivot Pins
  • Trigger Guard
  • A2 Pistol Grip
  • All necessary detents and spring

Buffer Tube Assembly

  • Buffer Tube (Mil-Spec 6 Position)
  • Castle Nut
  • End Plate
  • Buffer
  • Buffer Spring
Weight 5 lbs
Dimensions 28 × 5 × 5 in
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All NFA Rules Apply.

These items are controlled by the U.S. Government and authorized for export only to the country of ultimate destination for use by the ultimate consignee or end-user(s) herein identified. They may not be resold, transferred, or otherwise disposed of, to any other country or to any person other than the authorized ultimate consignee or end-user(s), either in their original form or after being incorporated into other items, without first obtaining approval from the U.S. government or as otherwise authorized by U.S. law and regulations.

It is the customer’s responsibility for understanding state laws regarding magazine capacities. Empire Tactical abides by all state regulations regarding the sale of high-capacity magazines. We DO NOT ship high-capacity magazines with firearms to certain states. Please see our terms and conditions for a list of restricted states.