Rifle Build Kit - 5.56 | BG Complete 16" Upper Receiver | 12" M-LOK HG |M4 6-Positon Stock Kit | BN LPK

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Product Code: BG1655612-BLK-IBOR-FULL-LPK
MSRP: $608.95
Sale Price: Sale Price: $339.95
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Rifle Build Kit - 5.56 | Builder's Grade Complete 16" Upper Receiver with A2 | M4 6-Position Stock and Buffer Tube Kit | Bare Necessities Lower Parts Kit

Builder's Grade Complete 16" 5.56 Carbine Upper Receiver | 12" M-LOK | BCG & CH:

This Complete 16 inch M-LOK upper receiver comes with our RTB 12 inch free float handguard and is built with only the best Mil-Spec components. The heart of this upper is comprised of a 4150 barrel and our black nitride bolt carrier group that is finished with an incredible polish, making the action smooth and easy to keep clean.

Caliber 5.56
Length 16"
Material 4150 Chrome Moly Vanadium
Profile M4
Finish QPQ Corrosion Resistant
Gas System Length Carbine
Gas Block Journal .750"
Dimpled? No
Twist Rate 1:7
Muzzle Thread 1/2x28 TPI
Weight 27.2oz
Barrel Extension M4 Feed Ramps
Target Crown 11 Degree

Bolt Carrier Group:

  • Enhanced 9310 Steel (Bolt)
  • 8620 Tool Steel (Carrier)
  • Bolt is shot Peened and MPI
  • All BCG components are pre-polished before being processed and then post polished for an incredible shine

Upper Receiver:

  • Machined from a Mil-Spec 7075 T6 forging Hard Coat Anodized per Mil-A-8625F, Type III
  • M4 Feed ramps
  • Made in the U.S.A.


  • 12" free float handguard
  • MIL-STD 1913 Picatinny rail on top
  • 3 M-Lok slots on 3 sides
  • Precision Machined aircraft grade aluminum, for high strength and weight savings
  • Hard Coat Anodized per Mil-A-8625F, Type III, Class 2
  • Clamp on system for easy assembly
  • Steel Barrel nut to resist movement under heat
  • 11.7 oz with barrel nut and hardware
  • 1.35" Inside Diameter
  • 1.63" Wide
  • Made in USA

Charging Handle:

  • Tried and True Standard Charging Handle
  • Forged 7075 Aluminum construction
  • Mil-Spec Type-III Hardcoat Anodized finish
  • Caliber - .223 / 5.56 / 300 Blackout
  • Made in the USA


Tactical Sport 6-Position M4 Stock Kit:

This polymer stock is made from impact-resistant, high-strength material.

  • Mil-spec Diameter Extension Tube Made from Aircraft Aluminum with Rolled Threads
  • Built for Heavy-duty Operations with Tightest Tolerance Control
  • Stock Assembly Complete with Action Spring, Buffer Assembly, Tear-drop Ring, and Castle Nut


Bare Necessities Complete AR15 LPK:

This BN Lower Parts Kit is what you need to build a custom AR15 from the ground up. Mil-spec dimensions and coating ensure the highest quality and correct component interface.

  • Safety Selector
  • Selector Spring
  • Selector Detent
  • Magazine Catch
  • Magazine Catch Spring
  • Aluminum Magazine Catch Button
  • Bolt Catch
  • Bolt Catch Detent
  • Bolt Catch Spring
  • Bolt Catch Roll Pin
  • Take Down Pin Take Down Detent
  • Take Down Detent Spring
  • Front Pivot Pin
  • Front Pivot Pin Detent
  • Front Pivot Pin Detent Spring
  • Trigger Guard
  • Trigger Guard Roll Pin
  • Buffer Retainer Detent
  • Buffer Retainer Spring
  • A2 Pistol Grip
  • Pistol Grip Screw
  • Pistol Grip Lock Washer
  • Trigger
  • Trigger Spring
  • Hammer
  • Hammer Spring
  • Disconnector
  • Disconnector Spring
  • Hammer Pin & Trigger Pin

***Disclaimer: This made-to-order product may include minor component substitutions of military-specification quality or better. These changes, potentially differing cosmetically from shown images, ensure enhanced quality and performance. This may include ambidextrous sling loop endplates or an upgraded extra power spring.
*This product is manufactured based on parts on hand. It may feature a standard or oversized trigger guard, depending on what we have available at the time. Also, it may have a standard curved trigger or a flat trigger.*

Flat or Straight Trigger


Please Note: Uppers may present light fouling from our quality control process and/or test firing