Guns: Let's Build an AR! - Part 3

Heller was affirmed, so to celebrate, I'm putting together an AR-15. This week - the lower gets assembled:

To put together the lower half of an AR, you honestly don't need much in the way of tools. You could get by with a hammer and some roll pin punches, although that means a long and tiresome struggle with several of the construction procedures. I do think it's best to supplement the basic items with a pair of locking pliers (the kind that have an adjustable bolt at the end of one handle), a vise (with appropriate padding or protection to avoid marring the finish of the lower), and some electrical tape.

There are lots of good resources on the Web if you need a step-by-step guide(Check out these two install guides from AR15.com, available here and here, and this video from Life, Liberty, Etc.). Here's a few highlights from my experiences:

The hardest part of the build for me was the installation of the trigger guard roll pin. It's not too difficult to start the pin in the hole with a hammer, but driving it all the way flush to the receiver's "ear" is a time-consuming process without a proper vise (I had to make do with a block fo wood and a couple decks of playing cards). You have to be careful, too, because it's possible to break the receiver here by putting too much stress on the "ears" of the trigger guard.

The second hardest part was the installation of the bolt catch assembly (the part of the AR that locks the bolt back after a magazine is emptied). It's frustrating at best to install with just a pin punch, and impossible if you don't have a small enough hammer or a long enough punch. I used an alternate method that worked flawlessly - cover the jaws of that pair of locking pliers with multiple layers of electrical tape to avoid scratching up the gun too much, and gradually press the pin in there by clamping it with the pliers. You might want to put tape on the receiver, too, just to make sure nothing gets scratched.

A part of the build that gets an undeserved reputation for being tricky is the assembly of the front pivot pin detent. Some simple precautions (like throwing a blanket over your work area in order to catch the detent in the event the spring launches it skyward, or at least working in a small uncluttered room) mean you'll never have to worry about losing the detent. I merely employed the pivot pin itself to depress the detent into the hole, and then slid the pivot pin into its final resting place.

All in all, if you know what you're doing and have the right tools, you could probably put the whole thing together in minutes. And at the end, you'll have the satisfaction of making something with your own hands, as well as the knowledge necessary to change out grips, stocks...even the trigger and hammer assemblies.

Next week - Sighting in and Test-fire