AR-15 Buffer Retainer

AR-15 Buffer Retainer

The buffer retainer is the small pin in an AR-15 lower receiver that stops the buffer and action spring from shooting out of the buffer tube when you open the rifle. This United Defense retainer is a replacement for one that is lost, worn or damaged. It also fits a lower you are building from a stripped receiver. Builders and owners doing their own maintenance usually keep a spare, because the part is small and easy to lose during a teardown.

Features

• Holds The Buffer In Place — When the upper receiver is pivoted open, the retainer catches the buffer so it and the spring stay inside the receiver extension.
• Stepped Pin Profile — A wide body seats in the retainer bore while the narrow tip rises into the buffer tube to stop the buffer's rim.
• Standard AR-15 Pattern — It is shaped to fit the buffer retainer hole found at the rear of a standard AR-15 lower receiver.
• Spring-Loaded Operation — It rides on the small buffer retainer spring underneath it, which pushes the tip up and lets you press it down to remove the buffer.
• Captive Once Installed — Threading the receiver extension, or buffer tube, into the lower holds the retainer in its bore so it cannot fall out.
• Black Finish — The dark finish matches the other small parts inside a typical AR-15 lower.
• Single Replacement Part — You receive one retainer, suitable for completing a lower build or replacing a missing pin.

Fit And Installation

To install, drop the retainer spring and then the retainer into the bore behind the magazine well, narrow tip up. Hold it down while you thread the buffer tube in until the tube's edge just covers the wide part of the pin and leaves the tip free to move. The retainer spring is a separate part and does not appear in the photograph.