How to Build an AR-15 Lower Receiver: Safety Selector and Pistol Grip

We’re now halfway through the steps for building our AR-15 lower receiver. We last left off with installing the hammer, and ready to move on to adding the safety selector and pistol grip. If you wanted to know what tools I’m referencing in this article, check out the tools and components post. The video embedded above is a visual walk-through of the steps covered in this post, but to make it more convenient, I’ve listed the time stamps that reference our specific steps.

(15:17) Step 7 – Safety Selector

This step is a real quick one. Take your safety selector and install it from the left side of the lower receiver while facing up as it would be in the fire position. It should rotate freely.

I told you it was a real quick one.

(15:52) Step 8 – Pistol Grip

Remove the lower receiver from the vise block, flip it upside down, and then secure it back onto the vise block. We will be utilizing gravity to our advantage installing the pistol grip upside down. Now, retrieve the safety selector detent, safety selector spring, pistol grip lock washer and pistol grip screw.

Let’s test the pistol grip. Grab it. Does it jiggle? Does it wiggle? If it doesn’t, then you have it secured in place properly. However, you still have to check the safety selector for proper function.

Flip the safety selector to safe, and with your hand over the hammer, pull the trigger. You should not be able to move the trigger much, and the hammer should not fall. Now switch the selector to fire, and with your hand over the hammer again, perform the same test. If the hammer is released when you pull the trigger, you are good to go.

We only have two steps left. The last post in the How to Build an AR-15 Lower Receiver series will walk you through installing the receiver extension, rear takedown pin, and, finally, the buttstock, and then we’re on to the AR upper build! Hang in there.