How to Build an AR-15 Lower Receiver: Trigger Guard

For those of you following the How to Build an AR-15 series (thus far, we’ve just finished installing the magazine catch), this article will cover installing the trigger guard. For visual reference for this part of the AR build, check out this video. I’ve included the time stamp for the segment of the video associated with this article.

I will be explaining how to complete this step with a block of wood, roll pin punches, and a hammer. But recently, I discovered the Roll Pin Pusher (R.P.P.) tool, which I’ll cover in more detail a later post.

(04:20) Step 2 – Trigger guard

PLEASE NOTE: It is extremely important that you maintain proper support to the “dog ear” tabs during this step. If you do not, you will risk breaking one of these tabs on your lower receiver. Yeah, not fun.

Remove your lower receiver from the vise block and place it on a hard, flat surface. Take your piece of wood and place it under the bottom “dog ear” trigger guard tab. Now place your trigger guard in between the tabs where it would be once it is installed. Using a small hammer and the properly sized roll pin starter, tap the trigger guard roll pin into the first tab and partially into the trigger guard, hence holding it in place.

Using a 1/8” roll pin punch, while supporting the bottom tab with the piece of wood, continue to drive the trigger guard roll pin into the trigger guard until it is flush on both sides of your AR-15 lower receiver.

I know you were careful, but did you break a tab off? Don’t panic too much. Just pick up one of these pistol grips and you will be back in action.

Our build is starting to shape up, isn’t it? Keep your eye out for the article on our next step: installing the bolt catch.