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Walker Defense Research Nickel Boron Bolt Carrier Group NI-B-556 Finish: Polished Satin, Fabric/Material: 9310 Steel, $10.00 Off w/ Free S&H

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Walker Defense Research Nickel Boron Bolt Carrier Group, 5.56x45mm NATO/.300 AAC Blackout, NI-B-556
Walker Defense Research Nickel Boron Bolt Carrier Group BCG, 5.56mm, .300 BLK, NI-B-556
Walker Defense Research Nickel Boron Bolt Carrier Group BCG, 5.56mm, .300 BLK, NI-B-556
Walker Defense Research Nickel Boron Bolt Carrier Group, 5.56x45mm NATO/.300 AAC Blackout, NI-B-556
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Walker Defense Research Nickel Boron Bolt Carrier Group, 5.56x45mm NATO/.300 AAC Blackout, NI-B-556
Walker Defense Research Nickel Boron Bolt Carrier Group BCG, 5.56mm, .300 BLK, NI-B-556
2 of 3 images
Walker Defense Research Nickel Boron Bolt Carrier Group BCG, 5.56mm, .300 BLK, NI-B-556
Walker Defense Research Nickel Boron Bolt Carrier Group BCG, 5.56mm, .300 BLK, NI-B-556
3 of 3 images
Walker Defense Research Nickel Boron Bolt Carrier Group BCG, 5.56mm, .300 BLK, NI-B-556

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Questions & Answers
Is this bcg chrome lined? Manufacturer Answer

It is fully plated with nickle boron.

by Walker Defense, Manufacturer, February 12, 2025
Will this work in my Anderson AM 15 carbine gas rifle? Manufacturer Answer

Yes, this BCG will work in your Anderson AM-15.

by Walker Defense, Manufacturer, February 12, 2025
View All Q&A You Have a Question? Ask!
Customer Reviews
Helpful Positive Review
My favorite BCG by David, Verified Owner, December 6, 2022
Out of all my BCGs (Aero Precision, Wilson Combat, Griffin Armament, and a couple cheap mil-spec ones), these Walker Defense Research ones are my favorite. Nickel-Boron is the only way to go for high-quality builds. These are some of the least expe...
Read More...
10/10 found this helpful
Helpful Positive Review
Outstanding BCG by Josh, Verified Owner, May 7, 2024
With so many AR15 bcg out there to choose from quality of the materials is important as well as craftsmanship. Walker Defense Research bcg checks all the boxes. Optics Planet customer service was excellent and my order was delivered in a very timely ...
Read More...
3/3 found this helpful
Helpful Positive Review
Perfection by JG, Verified Owner, April 28, 2024
Looking to get the smoothest BCG..look no further. Amazing product for any build or upgrade.
4/4 found this helpful
Read All 3 Reviews
Finish:
Polished Satin
Caliber:
.223 Remington, .300 AAC Blackout, 5.56x45mm NATO
Gun Make:
AR Platform
Gun Model:
AR-15, M4, M16
Hand:
Right
Condition:
New

Code: 3TI-BCG-RFG58MN45-NI-B-556

MPN: NI-B-556

List: $179.99Save $10.00
$169.99

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made-in-usa-flag Made in USA

Help support American manufacturing! Marked models of this product have gone through rigorous review and been certified by the manufacturer as Made in the USA.

Product Info for Walker Defense Research Nickel Boron Bolt Carrier Group

The Walker Defense Research Nickel Boron BCG delivers enhanced lubricity and cleaning characteristics through its polished nickel boron coating. The bright, satin finish serves as a functional surface that provides smooth, reliable operation while offering excellent wear resistance and notably easier cleaning.image

Each BCG undergoes rigorous small-batch quality control throughout production. Walker Defense Research hand-matches components, conducts High Pressure Testing (HPT), and performs Magnetic Particle Inspection (MPI) of each bolt. The gas key features enhanced staking using premium OCKS screws from Michiguns, ensuring reliable operation under sustained use.

The Nickel Boron BCG is compatible with direct impingement 5.56mm, .223 Rem, and 300 BLK AR-15 platforms. The polished nickel boron surface provides excellent wear resistance and smooth operation, making this BCG particularly suitable for users seeking enhanced reliability in demanding conditions.

Specifications for Walker Defense Research Nickel Boron Bolt Carrier Group:

Manufacturer: Walker Defense Research
Finish: Polished Satin
Fabric/Material: 9310 Steel
Carrier Material: 8620 Steel
Bolt Material: 9310 Steel
Caliber: 5.56x45mm NATO, .300 AAC Blackout, .223 Remington
Gun Make: AR Platform
Gun Model: M16, M4, AR-15
Hand: Right
Condition: New
Coating: Nickel Boron
Country of Origin: USA
Gun Type: Rifle

Features of Walker Defense Research Nickel Boron Bolt Carrier Group

  • Hand-Matched Component Fitment
  • High Pressure Tested (HPT)
  • Magnetic Particle Inspected (MPI) Bolt
  • Enhanced Gas Key Staking with OCKS Screws
  • Small-Batch Quality Control
  • Smooth, Low-Friction Surface
  • Superior Wear Resistance
  • Enhanced Cleaning Properties

Package Contents:

  • Walker Defense Research Nickel Boron Bolt Carrier Group

What firearm models does the manufacturer say Walker Defense Research Nickel Boron Bolt Carrier Group is compatible with?

The manufacturer suggests that Walker Defense Research Nickel Boron Bolt Carrier Group is compatible with AR-15, M4, M16

Walker Defense Research Nickel Boron Bolt Carrier Group Orderable Models

List of Orderable Models

  • Walker Defense Research Nickel Boron Bolt Carrier Group, 5.56x45mm NATO/.300 AAC Blackout, NI-B-556 , MPN: NI-B-556 , Code: 3TI-BCG-RFG58MN45-NI-B-556

Walker Defense Research Nickel Boron Bolt Carrier Group Unavailable & Discontinued Models

List of Unorderable Models

  • DEMO, Walker Defense Research Nickel Boron Bolt Carrier Group, 5.56x45mm NATO/.300 AAC Blackout, NI-B-556 , MPN: NI-B-556-DEMO , Code: 3TI-BCG-RFG58MN45-NI-B-556-DEMO
  • USED, Walker Defense Research Nickel Boron Bolt Carrier Group, 5.56x45mm NATO/.300 AAC Blackout, NI-B-556 , MPN: NI-B-556-EDEMO , Code: 3TI-BCG-RFG58MN45-NI-B-556-EDEMO-RE-B
  • USED, Walker Defense Research Nickel Boron Bolt Carrier Group, 5.56x45mm NATO/.300 AAC Blackout, NI-B-556 , MPN: NI-B-556-EDEMO , Code: 3TI-BCG-RFG58MN45-NI-B-556-EDEMO-RE-A
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