FREE SHIPPING & FREE RETURNS*

FREE SHIPPING on Over 250,000 Products

Shop now and get Free Value Shipping on most orders over $49 to the contiguous 48 states, DC, and to all U.S. Military APO/FPO/DPO addresses.

Enjoy our FREE RETURNS

We want to ensure that making a return is as easy and hassle-free as possible! If for any reason you are not satisfied with your purchase, simply return the item within 30 days of receipt, and we'll cover the cost of return shipping. Learn more about our Return Policy.

Shopping Cart
Spikes Tactical Lightweight Chromoly Castle Nut
As Low As $6.99 Save Up to 30%
View Product
Compare (0)
Most Helpful Positive Review Lightweight, Looks great!
If you have built a few lowers, you probably know how certain parts like castle nuts don't bring the same amount of fizzle as others. I am happy with the quality and I don't see why this castle nut wouldn't hold up to any level of normal use for a very long time. The finish is uniform and certainl...
Read More...
Most Helpful Negative Review They look nice, but are extremely loose.
I purchased both the standard and the lightweight version. The standard castle nuts work fine, but I always dislike that rough phosphate finish. The lightweight fancy ones must be made for spikes by a different company because they are extremely loose on every quality buffer tube ive tried fitting t...
Read More...
Show
Sort by
Filter by

Castle Nut

by JJ, Verified Owner from FL, United States Written on May 17, 2025
Well constructed item that will work across a variety of platforms.
Pros:
  • Well constructed
Cons:
  • Too slimline
Would recommend: Yes
Was it helpful to you? Yes | No

AR castle nut for Casper

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

Perfect Item!

by Gary Surratt, Verified Owner from WV, United States Written on October 8, 2024
Very happy with this item! Happy with the performance of the Optic Planet crew! It doesn't get any better than this. Thank you.
Pros:
  • All pros !!!
Cons:
  • No Cons
Best Used for:
  • AR15
Would recommend: Yes
Was it helpful to you? Yes | No

Great part for the price

by PeterB, Verified Owner from OK, United States Written on June 11, 2024
I need a castle nut and this worked and was cost effective
Pros:
  • Works great
Cons:
  • None
Best Used for:
  • ARs 10 & 15 and others
Would recommend: Yes
Was it helpful to you? Yes | No

Spikes Tact. Castle Nut, Chromoly

by Hennard, Verified Owner from PA, United States Written on November 12, 2023
Threaded on nice, light weight Chromoly, Staked nice A+.
Would recommend: Yes
Was it helpful to you? Yes | No

Spikes Tactical Lightweight Chromoly Castle Nut

by Steven Edwards, Verified Owner from NC, United States Written on November 3, 2023
This castle nut works great. No imperfections or burrs in the threads. But this one from Optics Planet!
Would recommend: Yes
Was it helpful to you? Yes | No

Spikes castle nut

by Dan, Verified Owner from OK, United States Written on October 25, 2023
Good quality, good price, can't beat a Spikes product for this price. Does everything it needs to do, and I will be buying more for future builds and spare parts. Buy with confidence, you won't be let down.
Would recommend: Yes
Was it helpful to you? Yes | No

Best on the market

by Jim, Verified Owner from CT, United States Written on November 1, 2022
In terms of a regular castle nut, this is my favorite. It's stainless steel, but it's but and a reduced weight with zero compromise in strength. Highly recommend if you are building yourself or trying to reduce weight.
Pros:
  • light
  • Strong
Cons:
  • None
Best Used for:
  • builders
  • reduce weight
  • matching black nitride
Would recommend: Yes
Was it helpful to you? Yes | No

Good Product

by Jake, from CT, United States Written on April 13, 2022
I used this in conjunction with the Spikes Tactical Mil-Spec Latch Plate in my latest AR build. This castle nut works fine and I've had no problems with it. It suits my needs, and I would buy it again.
Pros:
  • Cost & availability
Cons:
  • None
Would recommend: Yes
Was it helpful to you? Yes | No

Lightweight Castle Nut

by TX2A, Verified Owner from TX, United States Written on March 1, 2022
Excellent fit and finish at an economical price. I purchased this to replace an aluminum castle nut on a light weight build. It is way sturdier than the 6061 or 7075 available. The only other lightweight option is V7 but I am glad I went this route. For the price and weight difference you can’t beat it. The threads fit perfectly with my smoke composites carbon buffer tube, 2A armament, Aero Precision enhanced, and Vltor A5. The black nitride is well done and the lightning cuts are a nice touch. If you are in the market for light weight but don’t want to compromise strength give this castle nut a try!
Pros:
  • economical
  • Fit & finish
  • Sturdy light weight classy affordable
Cons:
  • Not milspec
Best Used for:
  • securing buffer tube
Would recommend: Yes
1 of 1 found the following review helpful.
Was it helpful to you? Yes | No
There are no reviews that match your criteria. Would you like to review this product?