AR-15 U-Build Complete 7.5" 223 Wylde Upper/Lower AR15 Kit
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BarDef U-Build Complete AR15 .223 Wylde 7.5 inch Pistol Kit. This Barrier Defense carbine length upper features a Mil-Spec M-16 bolt carrier group, phosphate finish, M4 profile barrel. The A3 upper will attach to any standard AR-15 lower receiver and comes complete with charging handle, forward assist, ejection port cover, bolt and bolt carrier assembly. With a 1 in 8" twist, the 7.5" pistol barrel chambered in .223 Wilde provides incredible close-in accuracy with a full range of ,223 and 5.56 NATO bullets. It's tipped with an A2 flash hider. This upper is a great platform for a red dot or flip-up sights (sold separately). Lower Receiver not included and can be purchased through an FFL dealer.

This product comes with the Barrier Defense lifetime warranty.

This kit also includes a complete buffer tube assembly. The buffer tube is machined from 6061-T6 aluminum. It includes Mil-Spec buffer, and spring. is tough to withstand years of use and abuse. The kit comes ready for you to assemble so you can brag that U-Built-It.

This Parts kit includes everything needed to build a complete upper and lower, except a stripped lower receiver. All parts are made to standard military specifications.

****Know your states laws when purchasing this item.


  • (1) 7.5" M4 Barrel 1:8 Twist/Pistol Gas System/Parkerized/Non-chrome lined (more accurate)
  • (1) BCG- 5.56 NATO Bolt Carrier Group 
  • (1) Slim Mlok Free Float Hand Guard 7"
  • (1) Lower Parts Kit w/Trigger & Hammer
  • (1) 750 Gas Block
  • (1) Pistol Length Gas Tube & Roll Pin
  • (1) Standard Receiver End Plate
  • (1) Mil-Spec/Commercial Castle Nut/Steel
  • (1) Buffer Tube/Alum.
  • (1) 3 oz. Buffer
  • (1) Buffer Tube Spring
  • (1) Mil-Spec Charging Handle Alum.
  • (1) Dust Cover
  • (1) Forward Assist & Roll Pin
  • (1) 1/2"x28 Thread Bird Cage A2 Muzzle Brake
  • (1) Pistol Grip/Black 
  • (1) Upper Receiver 5.56/.233/.300AAC, M4 Feed Ramps



Lower Parts Kit Includes

  • Bolt Catch
  • Bolt Catch Plunger
  • Bolt Catch Roll Pin
  • Bolt Catch Spring
  • Buffer Retainer
  • Buffer Retainer Spring
  • Disconnector
  • Disconnector Spring
  • Hammer
  • Hammer Pin
  • Hammer Spring
  • Magazine Catch
  • Magazine Catch Button
  • Magazine Catch Spring
  • A2 Pistol Grip
  • Pistol Grip Lock Washer
  • Pistol Grip Screw
  • Pivot Pin
  • Pivot Pin Detent
  • Pivot Pin Detent Spring
  • Safety Selector
  • Safety Selector Detent
  • Safety Selector Detent Spring
  • Takedown Pin
  • Takedown Pin Detent
  • Takedown Pin Detent Spring
  • Trigger
  • Trigger Guard
  • Trigger Guard Roll Pin
  • Trigger Pin
  • Trigger Spring


  • Item #: UB7W

AR-15 U-Build Complete 7.5" 223 Wylde Upper/Lower AR15 Kit

Price: $2,679.00
Availability: Out-of-Stock