Looking for a good set of AR-15 tools for an upcoming build? You’re not alone. And AT3 is here to help.
The AR-15 was innovative for a number of reasons, and chief among them was the concept of true modularity. While most guns of the era had hand-fitted parts (or at least required a gunsmith to change out parts), the AR-15 was designed to be built by multiple manufacturers and to be assembled and maintained by an armorer, not a gunsmith.
Could this be the real explanation for its enduring popularity? The AR is the most customizable gun in the world. You can put one together to meet any wild set of criteria and it isn’t overly complicated to do.
Good tools, though, will make any job better. You can crack open a basic carpenter’s toolbox and get to work, but you may end up marring some finishes or denting some of the more fragile pieces. So what goes in an AR-15 tool kit?
AR-15 building tools
Glad you asked. Let’s break it down.
To begin, look at the finished rifle. Where do parts connect? What can be removed by hand and what might require an actual tool?
Then look deeper. Some connections, like a delta ring or a castle nut, may not seem familiar–much less logical–to the average Joe. But the systems work.
And, while we’re on the subject, we’d like to add that building an AR-15 is right in the mid-range of the basic DIY scale. If you consider yourself handy in any way, the job is doable. If you’re utterly inept with basic hand tools, it may prove more challenging.
Flat-heads and Phillips-heads
Some components (like iron sights and optics) may require really common tools. For a gun kit, pick up a long screwdriver and a short-stubby one.
The long ones may be good for getting into grips or stocks (especially on shotguns). The short one offers more control and will keep you from slipping up and gouging aluminum.
Star-bits and Hex keys
Most AR-15 connections are a bit more specific, though, and require a hex key, or, as I grew up calling them, an Allen wrench. Allen wrenches come in the L-shaped bent metal variety, which works, and the full kit of interchangeable bits, which is a must-have.
Almost all of these kits will include star-bits, too. You can’t escape the need for those, either, as all of the accessory companies will have different connection types.
You’ll also need a variety of punches. These can be made from steel or brass. Brass is to keep you from buggering up steel (as the brass is softer than steel).
Punches come in a variety of diameters and each one corresponds to a pin in the AR that will need to be tapped in or drifted out. Thin punches bend easily, so be careful with them.
Some guns have roll-pins–thin sheets of steel that are rolled up to create the pin. These will often have a hole in the middle of the rolled-up pin (like the tube in a roll of paper towels) and you’ll need a roll-pin-punches to move them without damaging them. A roll-pin punch has a flat face with a small nipple that indexes into the roll pins void, and it keeps you from flattening out the top of the pin as you hammer it out.
Almost any hammer will do, but it is best to have a couple of options. Nylon hammers are very safe and keep you from doing too much damage. Brass hammers, too, have a similar use.
A steel hammer can be used to tap a punch, but shouldn’t be used to persuade stuck parts to move.
AR-15 assembly tools
There are a few tools that you’ll want that won’t have much use on any other gun. But odds are you’ll build a number of ARs, so they’re worth investing in. And they’re exceptionally useful for swapping barrels, forends, and changing out stocks and such.
AR-15 Bench Blocks
Now we’re getting more specific. The bench block is a very specialized AR-15 tool. It is designed to secure an upper when it is off the lower.
It is nothing more than a clam-shell design that fits inside a bench vise. They can be made of plastic, which is easy on AR-15 finishes. There are also aluminum blocks, too, that are specifically designed to hold barrels (and these will hold much tighter than any plastic options).
And a mag well block will help support the lower. It works in the same way, basically, and can mount to a bench alone, or you can get one that can be clamped in a bench vise.
The Delta Ring tool
The barrel is not so intuitive. Alignment is key, so you’ll need to pay close attention to how you work with the weld spring, the barrel nut, and the delta ring. You’ll also need a pair of snap-ring pliers to open the retaining ring.
Once the barrel is on and torqued correctly, you’ll want a hand guard. If you’re working with a clam-shell design, a delta ring tool can give you the leverage you need to pop them on or off.
Get a good AR-15 wrench
Once you dig into the DIY AR-15 supplies, you’ll see some odd-looking wrenches. These are super useful and are built on a multi-tool design. They’re meant to be just short of a one-stop solution for everything from installing a buffer tube to installing a delta ring to tightening a muzzle device.
You may find instructions for some parts ask for nuts to be tightened down to an exact pressure. To do this, you’ll need a torque wrench. This isn’t as complex as it might sound, and they’re very easy to read as you use them.
Once you get into a build, you’ll find you need some other items. One is going to be Loctite. This will help keep some parts from working loose during live fire.
Oil is good, too. And a rag. You may even want some old-school gun-grease.
And there is at least one measurement that you’ll need to check, even if you are confident that the parts you are using are the correct size. Find a way to check headspace. You can read more about that here.
Things to watch out for
Before doing any AR-15 build, make sure you have all of the parts. It wouldn’t hurt to have a schematic available to show you where everything goes and what each piece is called. And keep small containers handy so you can set down screws and fiddly parts without the risk of them rolling away.
And I’d add this note of caution. Work in a clean space. Springs can get away from you and some shoot tiny detent pins out of small holes and, if you’re lucky, you may hear them hit the floor.
If you don’t, they’re available. Those of us who do this regularly buy multiples and keep them on hand. Grab an AT3 FU-Bag if you are starting a build. The FU-Bag has all the most common lost parts that you may need.
That’s pretty much all you need. And patience. Some of the processes are incredibly easy, but not all of them.
And if you want to cut out a step in the process, pick up a set of tools. Again, you can’t go wrong with Wheeler’s complete set.
The essentials kit is not bad, either.
One Last Tip
If there’s anyone that knows the AR-15 platform, it’s the US military. As a special offer for our readers, you can get the Official US Army Manual for AR-15/M4/M16 right now – for free. Click here to snag a copy.