AR-15 Trigger Guard Roll Pin

Trigger Guard Roll Pin

This is the small pin that holds the rear of the trigger guard to an AR-15 lower receiver. It is easy to lose during a lower build and easy to damage when you drive it in, so a spare is handy on the bench. United Defense supplies it under part number MS16562-129. It suits builders finishing a stripped lower and owners replacing a bent or missing pin.

Features

• AR-15 Trigger Guard Fit — The pin passes through the two small ears at the back of the trigger guard area on the lower receiver and locks the guard in place.
• Slotted Roll Pin Design — A roll pin, also called a spring pin, is a tube with a slit along its length, so it compresses slightly as it goes in and then presses outward to stay put without threads or adhesive.
• MS16562-129 Part Number — The MS16562 prefix is the military-standard designation for slotted spring pins, which makes this part easy to match when you order replacements.
• Black Finish — The dark finish shown in the photo matches the look of a typical anodized lower receiver.
• Chamfered Ends — The slightly rounded ends help the pin start straight in the hole when you tap it home.
• Single Replacement Part — You get one pin, ready for a new build or to replace one lost or bent in an earlier attempt.
• United Defense Brand — This is a commercially made part from United Defense, not a surplus pull.

Fitting And Installation

The trigger guard ears are the most commonly cracked part of a lower receiver, and most of that damage happens while this pin goes in. Support the ear on the far side with a block or vise jaw while you drive the pin, and use a roll pin punch with a cupped tip so the end does not mushroom. A small starter punch or holder makes it easier to get the pin seated without scratching the receiver.