As I’ve mentioned, final assembly is truly the easiest construction you’ll do with your rifle. It hardly qualifies as construction, in fact. I’ll admit, I watched a video or two to ensure I was doing it right, but it’s so simple I could have figured it out without the assistance.
This is it. The last few pieces. In the grand scheme of things, final assembly is probably the least involved aspect of building an AR-15, but it is the point where this pile-o-parts finally takes shape as a true usable weapon.
Finally, I’ve managed to free up the necessary time to assemble the upper. I’ll be honest, I was a little nervous about this one, since in all my research, installing the barrel always seemed like the most particular and complex component. With all the specific torque figures, and alignment concerns, plus the fact that this is where the bang happens, I was very concerned about getting it right.
While gathering together the parts to build an upper wasn’t a cakewalk, getting the tools together was far easier. There are a few specialty tools that you can’t really get around needing, but mostly it is stuff you may already find in a well-stocked workshop or toolbox.
With a fully assembled and functional lower, the actual firearm, as far as the US government is concerned, is complete. Almost all of the determinations of caliber, power, size, and aesthetic are a function of the upper. For this portion of the build I was once again turning to a number of different manufacturers for a variety of different parts. The beauty of the AR platform lies truly in its modularity. Any parts that are labelled as Mil-Spec should be dimensionally compatible. True Military Specifications are a post for another time, however the term has evolved in context to mean a set of dimensions and tolerances that allow for interchangeability of parts between any number of manufacturers.
Parts were acquired, tools were assembled, research had been conducted, and my workspace was located. The preflight checklist was complete, it was time to actually begin.As prepared as I was, you’d think this was a huge undertaking somewhat akin to orbital rocketry, or deep sea exploration. Really, this whole process ended up feeling more like following directions on a Lego set, than truly “gunsmithing”. Though you want to make sure you’re paying attention, building an AR-15 is quite beginner-worthy.
While it doesn’t appear to truly matter where you start on the lower build, literally every guide I have seen so far begins with the magazine catch. I assume this to be rooted in the desire to have it adequately functioning so you can use a vice block to hold your lower for the remainder of construction. Again, this isn’t a bad idea. I’m going to look into it for further builds, but I managed to get through this entire run without one. It is a luxury rather than a necessity. The Spike’s Enhanced LPK comes with a milled aluminum mag catch button that comes without the drilled through hole found on most. This means that instead of simply screwing the catch into the button until it is flush, I inserted it until the screw bottomed out and backed it off until it aligned properly. Step 1: complete. I can get the hang of this.
With my parts acquired, it was time to dive in. My original plan was to create a video series that illustrated my freshly learned techniques with this, my very first build. This plan was…ambitious, to say the least. When it came time to build, I found myself plagued with A/V equipment failures. This was, of course, my first lengthy foray into detailed video production. Prior to this, I’ve only created a few short intro videos that have been uploaded to YouTube, and all of those were of a far less finicky nature. Unboxing a new flashlight, or quickly expounding a weaponlight’s shortcoming are insignificant next to creating a detailed instructional video for building a rifle. In the end, I found myself completing the build with only a fraction of the process successfully captured. Beyond that, I had another issue. You may have discovered it already, but remember, I was entirely naive about this concept only a few short months ago.
As I continue through this initial build, please remember that it is just that. My very first build. I’m taking you through this walkthrough not as an experienced builder, but as a first timer. I’m learning this right from scratch, and I’m hoping I can teach a few of you the same things with me. If you’re an experienced AR owner, please bear with me.
Once I had my AR Lower Receiver in hand, my research had begun. I had purchased what is known as a stripped receiver, meaning it did not contain any other parts at all. Simply a formed chunk of Aluminum. It obviously didn’t take me long to discover these necessary pins and springs are generally sold as a package deal called, appropriately, a Lower Parts Kit. Now these LPKs come in a number of flavors depending on what all you need included. If you want everything all at once from a single manufacturer, that’s obtained easily enough, if you’d rather get most of the generic pieces from one place, but would prefer a drop-in or otherwise specialty fire control group (trigger) or a more ergonomic grip, you can find LPKs without those specific portions.
The AR-15 lower. The heart and soul of the modern sporting rifle. This is where it all begins.
I’ve shot guns most of my life. Seriously. It’s been more than 2 decades since I first experienced the rush of pulling the trigger and hearing the controlled explosion designed specifically to propel lead downrange. I was 12 years old at a Boy Scout summer camp when I was first handed a single shot, bolt action .22lr and instructed in the art of aiming. Things have come a long way since then, and though I don’t get out to a range nearly as often as I would like, I still know my way around a firearm.