2020-10-24 (Sa) 80PercentArRifle

I started these instructions a couple of days ago. Please start there if you didn't already. This is the third, and final day in my posts that resulted in a successful receiver.

I drilled the trigger hole at the bottom of the fire control cavity. The instructions all recommended adhering a couple of strips of masking tape over the adapter that sits in the jig, but I found this unnecessary. When I clamped the jig together in the drill vise, I think that created enough tension to hold the adapter in place, but tape wouldn't have hurt anything. Most of the instructions I saw did not use wooden blocks to clamp evenly, and instead, they just had a couple of clamps wherever they would fit.

For the trigger hole, I drilled three times with the press and a 5/16" bit. The first and second holes were at the adapter's ends, and the third was in the middle. Once I had those holes drilled, I moved the vise to clear the oval section.
Trigger hole

I cleaned up my cuts again. On the sides, I used a Dremel and a sanding drum. Along the bottom ridges of the cavity and the holes, I used a drill bit. At the corners, I used a razor blade. I didn't get the crisp, neat lines of a manufactured receiver, but I believe it will be as functional as any mass-produced item.

There was no hammer pin or trigger pin in my gun kit, so I temporarily installed these parts by shoving drill bits into the holes and through the hammer and trigger. It held everything in place, and I aimed the camera so you can't see the drill bits sticking two inches out the back. When I tested the function, it all worked.
Trigger and hammer installed with the help of drill bits

Except for the bolt release lever, I followed these build instructions for the lower receiver assembly. Because of my receiver's style, the bolt release uses a unique pin and set screw instead of a roll pin that holds in place with friction. The receiver comes with the installation hex wrench, so that will need to stay in my repair kit.

When I displayed this for the picture, I had to set it on a raised platform because there are still drill bits sticking out the ejector port side. The white receiver and black parts look good to me. This gun is functional and complete, but I still want to paint the foregrip white to match and maybe paint some of the stock.
Assembled AR-15

The rest of the posts for this project have been arranged by date. First time here?

Completed projects from year 1
Completed projects from year 2
Completed projects from year 3
Completed projects from year 4
Completed projects from year 5
Completed projects from year 6
Completed projects from year 7

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