AR-15 Building Tools Part II

By Glen Zediker

After you have the “big” tools, which I should maybe call the essentials, most of the remaining tools are in the “handy” category. These things make some jobs easier, and life along with it… some are indispensable

One such tool I use often is a bolt disassembly fixture. Some springs on the AR-15 are stout and small. It’s difficult to keep them depressed for installations and removals without an extra appendage, and that’s what this item provides. The bolt disassembly fixture compresses the ejector. Without it, you’re trying to keep a tiny part compressed and still operate. An 0.375-inch wooden dowel piece will fit into the bolt face and compress the ejector, but it’s awkward to manipulate the retaining pin while trying to keep the dowel in place and the ejector under pressure. It can be done, but the actions are graceless.

Speaking of wooden dowels, a couple of small squares of soft wood are indispensable. Use these to back up parts for pin installations.

Masking tape should be a part of most projects. I use it to protect the receiver finish. The wisdom of its use is kind of like its original intent. Taking the time to prepare the surfaces prior to painting (or driving roll pins) pays off the first time there’s an “oops.” It happens in a heartbeat. I also use a strip of the wider variety to hold small parts in place while they’re waiting on installation. I learned this years ago working on motorcycles. It’s also a help to maintain the order of assembly.

Speaking of oops, a flat-black paint marker to touch up the shiny spots can make you feel all professional-like after pin installations, or when you forget the masking tape.

I think it’s important to polish the chamber on any AR-15. This is most easily done using a specialty tool, as is usually the case. I like the Flex-Hone. That tool, and some cutting oil, helps ensure spent cartridge cases eject with minimum damage and, yes, the polished chamber helps extraction the most, not feeding.


Here’s a simple rear sight spring tool. Use this to compress and hold the spring
while the roll pin is installed across its substantial gap. This is not an easy job,
and not possible without something like this to help.


Flying Springs

Two more assembly tools come to mind that become pretty much mandatory after one use. It’s really necessary to have a front takedown pin detent installer. It is only a round stock with a hole in it. You put the tool through the front hole in the lower, align its hole with that in the receiver, insert the detent spring and detent and then compress these pieces using a capture punch. Rotate the tool as you remove the punch and the tool will keep them captured. Carefully press out the tool using the front takedown pin as its replacement and the detent will engage its slot in the pin. Dandy.

Of course, even this isn’t certain. The detent is prone to careening wildly. And therefore, another valuable assembly tool for this operation is a plastic baggie to fit over the works in case the detent decides to launch. Otherwise, you’ll be sweeping and searching with a flashlight. I always keep a flashlight handy because strong light is the best means to locate such items. It’s amazing to me just how far these tiny springs can propel an item.

The second tool I’m thinking of helps with the installation of the magazine catch assembly. To finish this job, it’s necessary to compress the latch button fully inward so the latch mechanism can be wound down on its threads and establish the correct engagement. There is a phenolic tool that exactly fits the button recess, and the tool has enough height that the receiver can be flipped over and the plunger on the tool can be pressed against the bench top. This job then becomes very easy.


Xtra-handy for an important operation, this tool compresses the magazine latch button
so the latch can be wound to the correct orientation. Place the tool where it belongs,
flip over the receiver and press down.


This is a bolt disassembly tool from Sinclair. Works well. There’s even a hole
there to let the pin fall though. Good details.


There’s always something… Believe it or not, this is dang handy. It’s a rear takedown
pin pusher, or that’s what Glen calls it. Everyone has encountered stiff and stubborn
takedown pins, and now you won’t notice them.

Third Hand

Here’s one that’s genius. It’s a little more than a casual investment, but if you work on ARs with conventional plastic handguards, you know that removal and installation is another 3-handed job. It can be a bear to keep the Delta ring pulled down so each piece of the handguards can be removed, and it gets harder and harder with each failed attempt. A “handguard removal tool” uses a gripping surface and leverage to compress the Delta ring fully, and it’s easy to hold it fully compressed. The first time I used this I cried audible thanks to whoever invented it.

A rear sight spring tool is another must-have if you work on conventional (carry handle) uppers. The big spring covering over the sight post is a bear. Without some sort of tool, it’s not possible to install the roll pin. You have to keep the spring compressed above the level of the receiver pin holes so the pin can clear the bottom of the spring and enter the opposite side hole without getting bent to ruin. I dread this job. Specialty tools range from the simple to the complex. Simple ones look like a screwdriver with a “U”-shaped opening to allow the pin to pass by. Complex ones contain a threaded plunger that compresses the spring and holds it easily in place. A simple-style tool can also be made from a dowel with a hole drilled through it at an appropriate height, but you can guess there are levels of “works well.”

Grease, believe it or not, is an assembly tool—the thicker the better. Use it to retain springs and detents on rear sight assemblies, for instance. My choice is Plasti-Lube, the staple for M14/M1A lubrication. GI-issue grease (grease, rifle) works second best.

Of all the specialty tools, there’s one that might not get much use, but when it’s needed there is no substitute. It’s a carrier key staking tool. It’s possible, certainly, to effectively retain the screw heads after a sharp rap to a punch with a well-placed tip, but it’s also just as easy to get a really horrible-looking job. So if you always say, “I don’t care how it looks as long as it works…” you may not need a specialty tool. Otherwise, and also for the satisfaction of knowing the job was done effectively, it’s a good investment. There are different levels of performance, and correspondingly different costs. And, yes, the carrier keys should always be staked. Torque and glue aren’t adequate. I’ve seen quite a few carriers without staked key screws and that, in my opinion, is a half-done job. They also loosen, and when they do, malfunctions ensue.


This godsend is a handguard removal tool. It’s just too handy. The tab goes into
the mag well, the padded arms clamp around the ring and then lever it down.


This tool does a job no two people can manage without. It’s a—are you ready?—front
takedown pin detent installation tool. It holds the spring and detent in place while
the takedown pin is inserted.

Shameless Self-Promotion

The preceding is a specially adapted excerpt from The Competitive AR-15: Builders Guide, a book by Glen Zediker and Zediker Publishing. Check out or call (662) 473-6107.

200 South Front St.
Montezuma, IA 50171
(800) 741-0015

Champion’s Choice Inc.

201 International Blvd
LaVergne, TN 37086
(615) 793-4066


(MOACKS carrier key staker)
P.O. Box 42
Three Rivers, MI 49093
(269) 273-4867

Read More Up On AR Articles


Purchase A PDF Download Of The GUNS Magazine March 2014 Issue Now!

Leave a Reply

Your email address will not be published. Required fields are marked *

(Spamcheck Enabled)