Luth-AR Carbine Lock Ring/Castle Nut – AR-15/AR-10 Buffer Tubes

The Luth-AR Carbine Lock Ring/Castle Nut secures the buffer tube to the lower receiver and prevents the end plate from rotating on AR-pattern rifles. This is a replacement part for worn, damaged, or lost castle nuts during stock or buffer system installation. A properly torqued castle nut is essential for maintaining buffer tube alignment and preventing receiver extension loosening under recoil.

Manufactured from steel with a phosphate finish for corrosion resistance. Installation requires an AR-15 armorers wrench and staking tool. Torque to 35-40 ft-lbs and stake into the receiver threads after installation to prevent loosening. Compatible with mil-spec carbine buffer tubes.

• Part Type: Castle Nut/Lock Ring
• Compatible Firearms: AR-15, AR-10, and AR-pattern rifles with mil-spec buffer tubes
• Material: Steel
• Finish: Phosphate
• Installation: Professional recommended (requires torque wrench, armorers wrench, and staking)
• Includes: (1) Castle nut