• Compatible with both Mil-Spec & Commercial carbine buffer tubes
  • 0.13 oz. lighter than Mil-Spec castle nut
  • Machined staking notches
  • Made in the U.S.A.


  • Material: 4140 Chromoly
  • Finish: Phosphate
  • Weight: 0.53 oz.


  • AR-15 and AR-10 with carbine buffer tube


Building a custom rifle is a process full of decisions. You want the best parts you can afford, and it’d be best if your dream weapon didn’t require wheels for transport. Every part counts, some a little more than others. The job of the AR castle nut is to hold it together, literally. That’s a part you don’t want to skimp on. When you need a quality castle nut to marry your receiver and buffer tube, Spike’s Tactical offers a Lightweight Castle Nut that is ideal for most AR builds.

A Reduced Weight Option for Any Build

The Spikes Tactical Lightweight Castle Nut is a quality AR castle nut that weighs in at just 0.53 oz. That’s a weight savings of 0.13 oz. compare to Mil-Spec castle nut. This is a great option for those of you who need a lightweight castle nut for your build but must balance your desires against your budget. While you can find lighter castle nuts on the market, It’s not as expensive as some of the ultra-light offerings you’ll find so it’s perfect for almost any build, not just lightweight competition builds.

Precision Manufacturing, Quality Materials

Spikes lightweight castle nut is machined from U.S. Sourced 4140 Chromoly. The finish on these lightweight castle nuts is a hardy phosphate coating that blends flawlessly with your Mil-Spec blacks. It won’t be easily scratch, crack or peel and resists corrosion even in the harshest operating environments.

Every piece Spikes sends to market is precision crafted by their American team. Spike Tactical stands proudly behind its products with a Lifetime Warranty so you know they care.

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