AR-15 Tools, Maintenance and Repair

As either a hobbyist or professional there are some basic tools you will need to build and maintain your AR 15 rifle. You don’t need to start off with the most expensive tools out there, several of my first tools came from Harbor Freight, and it is what I could afford at the time. As you move on and figure out what you use most, you can get some better tools in needed. Sometimes you need to make do with what you have, be careful not to scratch or damage the weapon you are working on. Here is a basic list:

Ball-peen hammer
Nylon/brass hammer
Flat Tip
Needle-nose pliers
Bench mat, I have been using $5 yoga mats from 5 and below.
Bench vise
Padded vise jaws
Set of roll pin holders and punches in numbers 1, 2, 3, & 4
Barrel nut tool or combination armorer’s wrench
Buttstock tool (collapsible stock only)

I will call this Basic advanced. I know people will disagree, but if you are only going to do one or two rifles you can get the job done without them;

Lower receiver vise block
Upper receiver vise block set
Universal bench block
Handguard removal tool

The course material does a great job listing the more specific tools required to build your AR 15:

Barrel-Specific Tools:

Torque wrench (½” drive, 30 ft./lb. to 150ft./lb.)
Taper starter punch (3/32”)
Flat punch (⅛” to peen the swivel rivet)
Staking punch
Sight adjustment tool (specific to your type of sight, A1 or A2)
Gas tube alignment pin
Snap ring pliers
Breaker bar
Strap wrench

Upper Receiver Specific Tools:

Headspace gauge set – Field, Go, and No-Go
Rear sight elevation spring tool (for assembling the A2 sight)
Sight adjustment tool (for your type of sight)
Ejector removal tool

Lower Receiver Specific Tools:

.151 diameter punch (for locating trigger parts & installation)
Pivot pin detent installation tool
Bolt catch pin punch
AR-15 hammer trigger jig
Hammer trigger drop block (for adjusting the hammer & trigger)

Using the basic set of tools listed above will help you clean your rifle. First thing you need to do is to clear the weapon, ensure the bolt carrier group is forward and the safety is on. Push the front and rear take down pins out and separate the upper from the lower receiver. Then disassemble the upper receiver pull the charging handle back and remove the bolt carrier group. The charging handle will drop down as you continue to pull and can be removed from the receiver. On the left rear side of the bolt carrier, you’ll see what looks like a cotter pin, this is the firing-pin retaining pin. Pull the pin straight out and the firing pin will drop out of the bolt. Turn and remove the cam pin the bolt will now slide out. Make sure the gas ring gaps are not lined up and are in good shape. Next remove the extractor pin, the extractor will then come out. Inspect the extractor assembly spring and rubber piece to ensure good working order. Clean everything up with a small cleaning brush and solvent then wipe down with CLP. Re-assemble the bolt by putting the extractor and spring assembly back in the bolt and inserting the extractor pin, return the bolt to the carrier and insert the cam pin and rotate, insert the firing pin and the retaining pin. Run a couple swabs with solvent followed by CLP down the barrel. Insert the bolt group and charging handle to the upper receiver

After putting it all back together you should do a functions check:

1. Place the selector switch on fire and squeeze and hold down the trigger. You should hear the hammer striking the firing pin.
2. While still holding the trigger, pull the charging handle fully to the rear and let go to reset the hammer.
3. Release the trigger. You should hear a mechanical click. This is the disconnector releasing the hammer onto the trigger.
4. Place the selector switch on safe and try to pull the trigger. The hammer should not fall. If it does there is a problem with your selector switch and/or trigger.
Now that we have described the tools needed to build and maintain their AR-15-style rifle, listed instructions for cleaning your rifle and talked about the functions check. Let’s talk about various ways to store your rifle. Locked up and out of the wrong hands is the preferred way to store your firearms. Locking gun cabinets start at around $100 and can go as high as you wallet will allow. You can get wall to wall carpet, lights, and dehumidifiers. My thought on this is play big or stay home, I only want to make this purchase once so go as big as I can. I also want to protect my investments, firearms, from fire and theft. A locking gun cabinet might not do the job but a good quality safe can handle upwards of 1400 degrees Fahrenheit and any crow bar a thief can throw at it. You can safeguard your other valuables as well, not just your firearms.

U.S. Army TM 9-1005-319-10