AR-15 Buffer Retaining Pin

The AR-15 buffer retaining pin is a small but absolutely critical component in your rifle’s lower receiver. Often overlooked, this simple part is responsible for securing the buffer retainer and its spring, which in turn keeps your buffer and buffer spring correctly aligned inside the buffer tube. If this pin fails or is missing, your rifle will experience a catastrophic malfunction, rendering it inoperable. Every AR-15 owner, from casual plinkers to professional builders, needs a reliable spare like this one from Miami Shooters Supply to ensure their firearm runs flawlessly.

Key Features

• Manufactured from heat-treated, high-carbon steel for maximum durability and shear strength.
• Precision-machined to exact mil-spec dimensions for a perfect fit in any standard AR-15 lower receiver.
• Features a clean, phosphate finish that provides corrosion resistance and blends seamlessly with other components.
• Simple, drop-in installation requires no gunsmithing or special tools.
• Sold as a single unit, making it an ideal and affordable spare part for your maintenance kit.

Built For

This pin is essential for anyone assembling an AR-15 from a stripped lower receiver, as it’s a required part not included in most lower parts kits. It’s also a must-have spare for any responsible rifle owner’s maintenance and repair kit, as a broken or lost retaining pin will immediately stop your rifle from cycling.

Specifications

• Material: Heat-Treated High-Carbon Steel
• Finish: Phosphate (Parkerized)
• Compatibility: Fits all mil-spec AR-15 and M16 pattern lower receivers.
• Caliber Compatibility: Universal for all calibers in the AR-15 platform (e.g., .223/5.56, .300 BLK, 6.5 Grendel).

FAQ

Is this a necessary part for an AR-15 build?
Yes. The buffer retaining pin is a required component when building a complete lower receiver. Without it, the buffer retainer and spring cannot be installed, and the buffer assembly will not be secured.

What happens if my buffer retaining pin breaks?
If the pin shears, the buffer retainer and spring will be released, allowing the buffer and spring to travel freely into the lower receiver. This will cause an immediate and total failure of your rifle’s cycling operation until the pin is replaced.