| Industrial-grade steel nuts for a rock-solid buffer tube assembly. Proudly Made in the USA. |
Steel Castle Nuts for AR-15 and AR-10 Buffer Tube Assemblies
The castle nut secures the receiver extension (buffer tube) to the lower receiver and, together with the end plate, locks the assembly in place on AR-15 and AR-10 builds. This five-pack of steel castle nuts is suited to new builds, replacements, and keeping spares on the bench for multiple projects. Made in the USA, each nut is intended to hold the buffer assembly tight and resist loosening under repeated cycling.
Castle nuts are commonly staked to the end plate after installation to help maintain torque over time. Pair these with an AR15 mil-spec end plate or an ambidextrous dual loop end plate to complete the lower assembly.
Before ordering, confirm the nut matches your buffer tube and end plate so threads and fitment line up with your platform, and use a proper castle nut wrench for installation and torque. While you build, restock small parts like the buffer retainer spring ten-pack.