Anderson Manufacturing AR-15 Buffer Tube Castle Nut

Reliable Buffer Tube Security for Your AR-15 Build

The Anderson Manufacturing MIL-SPEC AR-15 Castle Nut is a critical component in securing the buffer tube and stock system to your lower receiver. Built from high-quality steel and Manganese Phosphate coated, this durable castle nut is designed to ensure a solid and reliable connection between the buffer system and the lower receiver—preventing loosening, maintaining stability, and improving long-term durability.

Key Features:

✔ MIL-SPEC Dimensions – Compatible with all standard AR-15 buffer tubes, ensuring a secure fit.
✔ Manganese Phosphate Finish – Provides corrosion resistance and long-lasting durability.
✔ Precision Machined for Secure Fit – Designed for proper torque application, allowing for a rock-solid buffer system attachment.
✔ Wrench Cutouts for Easy Installation – Castle turret-style cutouts allow a castle nut wrench to provide the necessary torque for a secure hold.
✔ Cutout for Staking – Prevents the castle nut from loosening over time, ensuring maximum reliability.
✔ Made in the USA – Manufactured to strict MIL-SPEC standards for uncompromising performance.

Why It Matters:

The castle nut plays a critical role in maintaining the integrity of the buffer system on an AR-15. A loose castle nut can cause instability, leading to malfunctions or premature wear. By staking the castle nut with the end plate, you mechanically lock it in place, preventing it from backing off during extended use.

For optimal installation:
🔹 Torque to 40 ft/lbs – No thread locker is required.
🔹 Position wrench cutouts away from the receiver – Align the smaller cutout with the end plate.
🔹 Stake the end plate into the castle nut – Lightly tap with a hardened punch to lock it in place while still allowing for removal if necessary.

Perfect for Any AR-15 Build

Whether you're building a new rifle or replacing a worn-out castle nut, the Anderson Manufacturing MIL-SPEC Castle Nut ensures a secure, long-lasting connection between your buffer system and receiver—so you can focus on accuracy, reliability, and performance.

✅ Upgrade your AR-15 with a castle nut built for strength and reliability!