Receiver Extension Nut (Castle Nut)

(140 reviews) Write a Review
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To secure lock plate on an adjustable stock for AR15, M4
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140 Reviews

  • 5
    Buy It

    Posted by Jacobe Conrad on Dec 17th 2020

    I know what you're thinking.... "It's just a castle nut.. they're all the same". I know... I use to be just like you. Let me tell you.... this is by far the BEST castle nut I have ever used. Well worth the few bucks more that it costs. The threads are so tight on this, screwing it on never felt so good. Spend the extra bucks and buy quality. You'll thank me later.

  • 5
    Castle nut

    Posted by Ryan M on Dec 7th 2020

    What can I say? Its metal, looks good, fits perfect, returning customer made!

  • 5
    Castle Nut

    Posted by Leo on Nov 25th 2020

    I ordered 4 to replace my aluminum castle nuts! These iron castle nuts are awesome

  • 5

    Posted by Justin Staniford on Oct 19th 2020

    I mean it seems well built , but the sticker package wouldve been worth the price of the castle nut! Would buy again and plan to do business in the future!

  • 5
    Its more to say..

    Posted by John Serrano on Oct 4th 2020

    The castle nut does exactly what it's supposed to do. no issues whatsoever, it's BCM what do you expect??

  • 5
    Top notch

    Posted by Austin G on Sep 4th 2020

    Top notch quality and service, they even sent me a few free BCM decals with my order. A company like this is hard to find nowadays.

  • 5
    Great Product

    Posted by Chris Radach on Aug 27th 2020

    Works like it should, timely shipping to Alaska

  • 5
    Castle Nut.

    Posted by Shane McNie on Aug 17th 2020

    It wasn't the prettiest castle nut. It wasn't the fastest castle nut. It didn't have the best luck with the lady nuts, but through sheer determination and persistence, this castle nut matured and became the most adequate means of attaching a receiver extension to a lower receiver. No complaints.

  • 5
    Castle nut for BCM lower

    Posted by Miguel Ortiz on Aug 12th 2020

    BCM makes great quality products, I experienced this when replacing the SBA3 brace on my BCM lower. First, their stake job was by far the best I have come across; the only way I could remove that castle nut was by cutting it off. Purchased another castle nut from BCM, great quality and fast shipping. I also purchased the BCM qd endplate and was easy to stake. Love BCM products.