Whether it’s your first AR or your fifth, at some point many owners (or would be owners) decide to assemble from parts instead of buying a finished manufacturer’s product.
One of the frequent questions we get asked is some iteration of, “I’ve never even owned an AR before. Is it hard to build one from scratch on my own?” Though it may seem overwhelming at first, assembling an AR piece-by-piece isn’t as complicated as it might seem. It really is just a bunch of small, easy steps. If you can pay attention to detail, follow instructions and have the right tools, you can have your first range-ready AR built in a couple of hours. Many people – including yours truly – have built ARs without any prior training, education or special skill. There are plenty of online instructions out there that can walk you through the process step-by-step, and the folks at Next Level Armory are always available to give advice and steer you in the right direction if you run into trouble.
Also: If you haven’t yet checked out the more general article, Planning Your First AR Build? Here’s How to Get Started, now would be a good time.
Build vs Buy
There are hundreds of manufacturers out there making quality ARs, but building your own can give you the flexibility to use exactly what components you’d like. Some start with a kit that includes everything needed to complete the firearm. Someone else with more experience and familiarity with the hundreds of manufacturers out there might build a completely custom AR right down to the trigger pins. Another person might find some middle ground in-between. Whatever your comfort level with part selection, Next Level Armory can accommodate you.
While cost may not be the main factor for everyone, there certainly can be a cost savings to buying your AR in parts rather than off the shelf. Why?
- Manufacturers are required to pay an 11% federal tax on each completed firearm they sell, which is baked into the price when you buy off-the-shelf.
- You can avoid third party markup on OEM products (where one “high end” brand purchases unbranded parts from a different manufacturer, but marks them up significantly), by sourcing parts from the original manufactures.
The other cost consideration is that by building your own, those component purchases can be spread out, essentially allowing you to finance your AR over time instead of one big expenditure (or at least that’s what I told my wife).
Customization may be the main reason people build instead of buy, but one of the best benefits is the technical knowledge gained. There’s no better way to understand the ins and outs of how your firearm functions than by assembling it piece by piece. If you ever have problems with your rifle, you’ll be much better equipped to diagnose and remedy the problem without necessarily needing to visit a gunsmith.
The Right Tool for the Job
Of course, you’re going to need some equipment to properly assemble your AR. You may be able to find some of these tools bundled together as part of a gunsmithing tool kit, otherwise they can all be bought individually. Many can be found at your local hardware store, while Next Level Armory has many of the gunsmithing-specific tools in-stock. While you certainly will need to factor in the cost of these tools when comparing the price of a pre-assembled AR vs building yourself, I would suggest these tools should be purchased by every AR owner to help with ongoing maintenance and modification. It’s also worth noting that many of the tools are general-duty items that can also be used for multiple everyday applications – stuff that every home toolbox should have anyway.
UPDATE: No need to wait! If you prefer to build-up your own tool inventory over time, but get started on an AR now, Next Level Armory does have toolkits available for rent that contain the main items needed to assemble an AR, so stop on by!
So here’s what you’re going to need…
It doesn’t have to be pretty – my humble workbench was hand-built by my wife’s grandfather. It’s seen many seasons, but does the job just fine. All you really need is a flat table or workbench sturdy enough to mount a standard bench vice to (if it doesn’t have one already). Also, you’ll be working with some very small parts, so make sure the area is well lit. A second light source – like a mountable reading light – will come in very handy when you invariably cast a shadow right where you’re trying to see. Lastly, you’ll want it to be clean.
Many parts of an AR are held under constant tension by springs. A detent pin flying into your eye at high velocity is sure to ruin your day, and potentially a lot more. Why take a chance?
Upper and Lower Vice Block
You obviously don’t want to clamp down directly on your gun parts with a vice, so these vice blocks are built to hold your AR upper or lower firmly in place without the vice jaws touching the part itself. They’re often sold as a package, with a magwell block for the lower and a clamshell block for uppers. However I quickly found out the clamshell blocks aren’t compatible with many non-milspec upper receivers. Save yourself a lot of headaches and get a steel rail-style block, or if you want to go all out, the more expensive Geissele Reaction Rod. You’ll be good to go with practically any AR upper receiver.
Like many firearms, most of an AR is held together using various sizes of roll pins. Those pins need to be hammered in place, and good set of roll punches are the best way to do it. Make sure you also get a 1/16″ punch if your set doesn’t come with one. It makes a good “slave” for the small roll pins.
AR Armorer’s Wrench/Tool
This AR-specific multi-tool is used for several tasks, from installing mil-spec barrel nuts (which many after-market handguard manufacturers still utilize), as well as the castle nut on your buffer tube. They also have cutouts in various sizes that work well for timing muzzle devices, etc.
A small, two-sided hammer mainly used for driving roll pins home, but you’ll use it for all kinds of other things. One side of the head is usually made of metal for hammering pins, while the other side is a softer nylon or plastic.
Most manufacturers seem to stick to Allen or Torx-head screws, so you’ll want a wide range of sizes in those types of bits. But I’ve seen some components use Flat-head or Philips as well.
ARs utilize a lot of small components, and a small set of needle-nosed pliers work much better than your fingers when it comes to holding something in place.
Barrel nuts must be tightened within specific tolerances. You’ll need a torque wrench to ensure you’ve tightened things up just right.
Torque Wrenches can break or become improperly calibrated if misused. Don’t take the chance. Use a breaker bar to do any of the non-specific loosening or tightening you might require.
Anywhere two different types of metal touch – in this case usually steel and aluminum – grease should be applied in order to assure they don’t seize or corrode together over time.
Loctite or similar threadlocking compounds are liquid products applied to screws to keep them from coming loose over time. You’ll find this being called-for with many free float handguards, or when it comes time to mount optics.
Good to Haves
While the above items will give you what you need to get things built, here are a few items I’ve found very handy. The more builds or modifications you think you might be doing, the more useful and worthwhile it becomes to invest in some of these items.
Roll Pin Starter Punch Set
While I got by with needle-nosed pliers for my first build, these starter punches make life SO MUCH easier when it comes to getting the roll pins started. They have hollow tips that hold the pin where you want it, while at the same time give you something to hammer. Once the pin is started, it’s much easier to finish with a standard punch.
1/4″ Clevis Pin
Installing the front takedown pin is a tricky process. We’re simply not equipped with enough hands. It’s usually one of the last steps of a lower build and the one I used to least look forward to. Then I came across this video I found on YouTube showing how a $2 clevis pin from your local hardware store makes it a breeze. You’re welcome!
Crowfoot Wrench Heads
Some barrel nuts simply require a crowfoot wrench head – usually 1 1/4″ and 1 1/3″ – attached to your torque wrench to install barrel nuts. If you’ve already got some in your toolbox, great. Otherwise I recommend you buy one at a time only as needed.
Sometimes you need to hit things on your gun hard without marring the finish.
Some manufacturers require that certain screws be tightened within minimum or maximum tolerances. However this is mainly used for mounting scopes, etc. so it’s not crucial to have for a build.
I can’t tell you how many times a thin, flexible piece of metal has been just the ticket. They certainly make installing the gas tube into the gas block a lot easier.
Eventually you’ll want to get a small part organizer to store the little extras that tend to accumulate.
No, I’m not suggesting you need a dedicated “gun freezer”. Most parts of an AR are either made of aluminum or steel. These two metals expand and contract at different rates, so a little time in the freezer can do wonders to help separate really tight-fitting parts. Science!
Seizing compounds like Loctite are often applied to screws to ensure they don’t become loose over time. That’s great until you want them to come loose. The high heat level from a heat gun will re-soften the previously applied compound. Only works for low strength (blue) products.
If you ever need to remove a super-tight barrel and the freezer trick just isn’t working, a foot-long piece piece of wooden doweling will make the job much easier. Insert through the back of the upper receiver until it contacts the barrel extension, and hammer away to push the barrel out. Make sure to have someone there to catch it, or at least something soft in place for it to land on.
Some roll pins need to be punched at awkward angles that have your hammer swinging dangerously close to other parts. A little painter’s tape is a great way to non-permanently cover and protect an area of your receiver when you’re worried an errant hammer swing might take off some of the finish.
Gunsmith’s Touch-up Pen
Invariably, you’re going to scratch something. While your AR is no doubt going to get banged-up over time out in the wild anyway, there’s no glory in your first ding coming from an errant punch – (especially when it’s someone else’s baby you’re working on). I gouged the heck out of my first lower while trying to hammer the bolt catch release pin in place without the benefit of some of the items mentioned here). You learn to avoid these slip-ups, but even to this day I still have the odd “oops” moment. This black touch-up applicator will help cover and protect those awkward blemishes on your otherwise shiny new AR.