ATI A5101020 AR-15 Castle Nut Mil-Spec Steel Black Threaded

The Advanced Technology A5101020 AR-15 Castle Nut delivers mil-spec reliability for securing buffer tubes on AR-15 platform rifles. This precision-machined steel component ensures proper torque retention and maintains zero movement under recoil stress.

What Makes This Different

Unlike aluminum alternatives that can strip or crack under repeated installations, this steel castle nut features hardened threads rated for 40+ ft-lbs of torque. The mil-spec dimensions guarantee compatibility with all standard AR-15 buffer tube assemblies. Black oxide finish resists corrosion while providing a professional appearance that matches most tactical builds.

Key Features

• Mil-spec steel construction prevents thread stripping and cracking
• Standard 1.185"-16 TPI threading fits all AR-15 buffer tubes
• Six staking notches allow proper alignment with gas tube
• Black oxide coating provides corrosion resistance
• Precision machined to +/- 0.001" tolerances
• Compatible with carbine and rifle-length buffer systems
• Torque rating exceeds 40 ft-lbs for secure installation

This castle nut maintains buffer tube alignment during rapid-fire sequences and sustained shooting sessions. Law enforcement armorers specify steel castle nuts for duty rifles due to their resistance to loosening under heavy use. The precise threading eliminates wobble that can affect accuracy in precision shooting applications. Competition shooters rely on the consistent lockup for maintaining point of impact across match stages.

Technical Specs

• Material: Heat-treated carbon steel
• Threading: 1.185"-16 TPI (mil-spec)
• Finish: Black oxide coating
• Outside diameter: 1.37 inches
• Height: 0.38 inches
• Weight: 0.8 ounces
• Torque specification: 35-40 ft-lbs
• Staking notches: 6 positions
• Compatibility: All AR-15/M4 buffer tubes

Professional builders choose steel castle nuts for builds requiring maximum reliability and longevity. The Advanced Technology A5101020 meets TDP specifications while offering superior durability compared to standard aluminum components. This essential component ensures your buffer system remains secure through thousands of rounds.