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RTB Nickel Boron Bolt Carrier Group - 158 - MPI - M16 BCG (5.56)
RightToBear.com Nickel Boron 158 5.56 Bolt Carrier Group

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MSRP $169.99
SALE PRICE: $129.99
Savings: $40.00

Stock Status :(Out of Stock)
Product Code: NIBBCG-2

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Nickel Boron Bolt Carrier Group – 158 – MPI M16 BCG (5.56)

This M16 Bolt Carrier Group drops right into your M16, AR15 or M4 platform rifle. We source our components from manufacturers that meet or exceed Military Specifications. All parts are machined and properly heat treated to Mil-Spec followed by complete Nickel Boron coating with UCT’s Exclusive EXO Technology.

Our Nickel Boron Bolt Carrier Group is specifically coated to allow your rifle to operate smoothly, be easily maintained, and work longer without being cleaned. We offer a 100% money back guarantee. With top quality companies that we utilize to plate our BCG’s such as the UCT bolt carrier group, and WMD bolt carrier group, we are confident that each component that the BCG is made of will successfully work on any quality AR15 rifle. Every component, from the extractor to the firing pin, is made with exacting specifications to meet military standards and provide the best control possible. The 158 MPI BCG is engineered to fit and work with the AR15, M4, and also as a M16 BCG.

Order from our site today and experience the quality products we have to offer at great prices. If you are not satisfied, take advantage of our 100% money back guarantee. We inspect and test fire every unit before packaging. Some light fouling may be present.


  • Coated Inside & Out With UCT's EXO NiB
  • Milspec Carpenter No. 158® Steel (Bolt)
  • 8620 Tool Steel (Carrier)
  • Mil-Spec Extractor Spring, black extractor insert, Viton O-Ring
  • Tool Steel Extractor
  • Shrouded Firing Pin
  • Mil-Spec Gas Key (4130 Steel) attached with Grade 8 hardware and Properly staked
  • Bolt is shot Peened and MPI
  • Carrier is polished before plating for increased lubricity
  • Limited Lifetime Warranty

Average Rating: 5 of 5 Total Reviews: 38 Write a review »

  0 of 0 people found the following review helpful:
First Purchase July 17, 2017
Reviewer: Bradford Smith from Tyler, TX United States  
Received my BCG on time. Looks good. Properly staked. Haven't shot it yet. But I predict a good result.

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  0 of 0 people found the following review helpful:
Nickel boron bcg July 17, 2017
Reviewer: Jarrod  
Great product and fast shipping would recommend to anyone

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  0 of 0 people found the following review helpful:
Great product June 25, 2017
Reviewer: Bud H. from suffolk, VA United States  
Just had the chance to try out the nickel boron BCG with 158 bolt and I have to tell you it works flawlessly. Very smooth and slick action no hiccups with firing and cycles with ease. The fit and finish of this BCG is beautiful no tool makes with a very sleek finish.

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  0 of 0 people found the following review helpful:
Very Nice June 10, 2017
Reviewer: J K from North East United States  
This BCG looks very nice and is very slick. Haven't used it yet, but I'm sure it will be great judging by other reviews. Also shipping was very fast from RBA, definitely be coming back again.

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  1 of 1 people found the following review helpful:
Reallyk nice! April 27, 2017
Reviewer: Anonymous Person from Snohomish, WA United States  
This is the second one of these BCGs that I've bought from these guys. REALLY nice parts. They look great, they work great and they're quite easy to keep clean. If I ever need another BCG, this is what I would buy. Definitely worth the cost, even when not on sale.

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