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Reviews & Ratings for AT3 Tactical Castle Nut for AR-15 Buffer Tubes — 36 reviews

(36 reviews)
AT3 Tactical Castle Nut for AR-15 Buffer Tubes
AT3 Tactical Castle Nut for AR-15 Buffer Tubes
As Low As $6.99
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Most Helpful Positive Review SHINNY Black
I got this for a build where I was wanting to match up the blacks. The ATC castle nut is very black, but was TOO shiny/glossy. So if you want a castle nut that is turely black AND shiny this would be for you.
Most Helpful Negative Review Not Shiny Black
I read the review, and expected a shiny, black castle nut. I received 3 dull, flat black castle nuts. These were on back order for over 3 months, and when they arrived, not even meet the description. They are steel, and work fine, but the color for my guns will not work. Now I have to order from...
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castle nut

by Trevor Bakich, from VA, United States Written on January 13, 2026
Works as should, quick shipping and product came in with no flaws
Would recommend: Yes
Was it helpful to you? Yes | No
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Great Replacement Parts

by Wob1978, Verified Owner from TX, United States Written on December 10, 2025
Ordered this to replace a part I messed up on a rebuild. Works perfectly.
Pros:
  • Fit & finish
Cons:
  • None
Would recommend: Yes
Was it helpful to you? Yes | No
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Castle Nut for AR-15 Buffer Tubes In Flat Red

by fox, Verified Owner from WI, United States Written on May 16, 2025
Not certain if the color is painted or anodized or something else but it's nice just the same.

Deliveries are long because a lot of items sold are not stocked, but I waited in order to finish my build.
Pros:
  • Performs as designed
Cons:
  • Not certain of type of color finish
Best Used for:
  • Color coordinated builds
Would recommend: Yes
Was it helpful to you? Yes | No
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Red Castle Nit

by fox, Verified Owner from WI, United States Written on May 8, 2025
Finishes off my 10mm nicely. Like the duller red finish on it too.
Pros:
  • Like the finish and color
Cons:
  • None
Best Used for:
  • Any AR .223/5.56 or similar upper
Would recommend: Yes
Was it helpful to you? Yes | No
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AR castle nut for Casper

by BMB, Verified Owner from GA, United States Written on March 21, 2025
Worked as it should. Easy to use. Good quality as I always expect from Optics Planet! You guys are the best!
Would recommend: Yes
Was it helpful to you? Yes | No
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castle nut

by scotty, Verified Owner from CA, United States Written on March 18, 2025
What I needed to complete my build.
I would recommend this item to anyone who is interested into this kind of thing.
Would recommend: Yes
Was it helpful to you? Yes | No
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Matched well

by SS, Verified Owner from FL, United States Written on February 6, 2025
Matched the color I needed as I continue to build my black and flat earth colored AR
Would recommend: Yes
Was it helpful to you? Yes | No
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castle nut

by sharpshooter33, Verified Owner from OH, United States Written on January 30, 2025
Works like a castle nut should. No problems with threading on buffer tubes ive used
Would recommend: Yes
Was it helpful to you? Yes | No
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Mishaped/out of round

by Jimmy, Verified Owner from IA, United States Written on January 28, 2025
This castle nut would not thread on very easily and it clearly was bent/out of round. Ended up using a different castle nut and it threaded on just fine to the tube without excessive drag and binding like this one did. Not worth dealing with CS for a return since there is a restocking fee & I have to pay to ship it back. Very disappointing.
Pros:
  • None
Cons:
  • Poor Quality Assurance
Would recommend: No
Was it helpful to you? Yes | No
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castle nut

by Jon Park, Verified Owner from FL, United States Written on January 25, 2025
Perfect fit snugs up well to secure stock to lower
Would recommend: Yes
Was it helpful to you? Yes | No
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