Sunday, October 21, 2012

Tonight's Project - An AR-15 Lower Build

I decided that tonight was the night to finally build and complete my AR-15 Lower.

Having never done this before, it should get interesting.

Wish me luck.

Update 1: Ok, The Mag catch is in. So far, so good.

Update 2: Whew, that took some work, but the bolt catch is now in. That roll pin did not want to cooperate.

Update 3: Now it's looking more like an AR lower.

The front pivot pin, detent and spring installed so easily it was surprising.

Trigger, disconnector, hammer and selector were then all installed when I realized there was an extra spring sitting with the outstanding parts...the instructions I had that detailed the assembly process quite subtly glossed over a mention of installing the disconnector spring.

Drat. So I took it all apart, added the spring and put it all back together. Having done it once before it was a tad bit easier to do. Then I added the pistol grip and screwed it into place.

Unfortunately, The roll pin for the trigger guard refuses to go in and Natasha has ordered me to cease all hammering noises and assorted vocabulary enhancements this late at night.

I'll have to work on it tomorrow.

Also, anyone have any idea what is the size of the Allen wrench to screw in the front of the Magpul trigger guard screw? Nothing I have seems to fit.

Update 4: And, with the exception of the trigger guard, I'm done!

Total build time, including running around looking for the right tools occasionally, battling evil roll pins and assembling and reassembling the trigger components, taking pics and blogging the experience was two hours and forty minutes.

Certainly it was an interesting exercise, and I now know a lot more about AR-15 lowers than I had before.


Kevin said...

I'm assembling a lower, too. The trigger guard roll pin was also recalcitrant, but I finally beat it into submission. The roll pin for my bolt catch performed a successful escape. I'm waiting for a new bolt catch pin to finish my assembly.

Aaron said...

Yep, I just completed beating my trigger guard roll pin into submission. Did I mention I'm really starting to hate roll pins?

Now I just need to find the right sized allen key for the trigger guard screw and I'm all done.

Good luck on the bolt catch pin, it took quite a bit of effort to get mine into place.

Scott said...

Is the allen metric or english?

Maybe one of those AR swiss-army-knife type tools is in order?

Aaron said...


No idea. I've tried with my imperial set of keys and the smallest is just a smidgen too small and the one up from that is a smidgen too big. Next time people, think Philips head fer crying out loud.

It would be nice if they told you the size, or even threw one of the appropriately-sized keys in with the trigger guard now wouldn't it?