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SO: You wanna build an AR-15 (but need tools)

This guide assumes you already have the AR-15 parts you want (I have resources for suggested parts lists elsewhere but my homie that keeps that up wants it to be a living document so its not readily accessible to just CopyPaste here).

This guide also assumes you know how to put the damn thing together. I'm not listing the instructions out for that here (yet. idk) Do your own homework and find videos and guides on how to do it.

This guide lists out the various tools you will need and why you will need them. There will also be a label next to each tool header of [VITAL] for absoutely necessary components, [SUGGESTED] for parts that are heavily suggested but technically not required, and [OPTIONAL] for parts that may or may not apply to your build. I will try to order this list vital-components first. There will also be a label next to each tool header of [UPPER] for tools only used on upper recievers, [LOWER] for tools only used on lower recieversm, and [FULL GUN] for tools used on both.

For each tool type there will be a list of possible things you can purchase to fullfill the tool need. They will be labelled with the name of the item, the approximate price, and a label of either [KINDA GUCCI] for more expensive but robust equipment, [DAMN FINE] for tools that will likely stand the test of time but won't break your wallet, and [GOOD NUFF] for tools that will be sufficient for an AR build but may be less reliable for other tasks and over long periods of use. Options will be listed in order of price, with exceptions for multi-use tools (like upper/lower combo blocks, punch sets that come with roll pin starters, etc). Keep in mind, this guide is still very budget-focused! there are far guccier options for many of these tools that cost Thousands of dollars but thats outside my scope.

This guide is built both out of my own experience buying budget tools for my first AR-15 build, and the knowledge of several of my friends who have built and worked on their own ARs. Some of them like very fancy tools, and I politely asked they keep their suggestions within a reasonable budget lol.

The links provided here are not the only place to find the product I mention! Check in-person at your local hardware stores first for the non-gun-related tools to see if theyre cheaper there so you dont have to pay shipping. Check your local gun store for gun-related tools (but make sure they aren't overcharging you lmao. scumbags love to mark stuff up).

LET US BEGIN.

A Bench Vice [VITAL] [FULL GUN]

You will need a bench vise to build any AR-15. Many components need to be torqued down (tightened) to a specification that frankly, most people cannot accomplish by holding the gun against a table or between their legs. This must be complemented with a method of holding gun components (that'll be the next item on the list).

IT IS PRETTY MUCH FUCKIN MANDATORY that you bolt the vise down to a sturdy bench or table. I have personally attempted to torque down a buffer tube with a non-bolted vise and I fucked up my castle nut really badly and had to purchase a new one. Do not get a jewlers vise or a woodworking vise that clamps to the table or uses a suction cup. They will likely not be enough to withstand the forces you will need to exert on them when torquing down components. If your vise is stupid fucking heavy and massive it may not move, but that will not be the case for any of these suggested options. Here is a video on how to mount one in a good position on a workbench. If you're installing it to a flimsier MDF/Chipboard desk, push it back like 2" from the edge at least. Don't install it on any bench thinner than like, 3/4", or anything hollow-core.

If your vise swivels or rotates that will make it far easier to get your gun parts to a good angle for working them, but it is not strictly necessary. Generally, a vise with 3" jaws should be good enough.

Suggested Options:

Something to Hold the Upper [VITAL] [UPPER]

Dont clamp your upper directly in the vise. These components provide a way to hold the upper in the vise reliably, without damaging it. This is necessary for when you torque down your barrel nut and muzzle device. Vise blocks that clamp over the upper are not listed here, as they are unreliable and can exert excessive force on the upper.

Suggested Options:

Something to Hold the Lower [VITAL] [LOWER]

Dont clamp your lower directly in the vise. These components provide a way to hold the lower in the vise reliably, without damaging it. This is necessary for when you torque down your buffer tube. Vise blocks that clamp over the lower are not listed here, as they are unreliable and can exert excessive force on the lower.

Suggested Options:

Torque Wrench [VITAL] [FULL GUN]

your gun goes boom, you want to make it go boom the right way, you torque it to spec so it doesnt fly apart in your hands or turn into a pipe bomb.

PLEASE WATCH A VIDEO ON HOW TO USE A TORQUE WRENCH. Once you set the torque, push on the damn thing until it goes "click" and kinda slips forwards a little, thats how you know it's met torque. Mount any wrench heads at 90 degrees to ensure that youre not fucking with leverage in a way thats gonna affect your effective torque. See this video for an example of how to mount any odd wrenches you might need, and this video for how to use a torque wrench in general. Make sure your torque wrench has settings for 20 ftlbs, and 80 ftlbs. make sure your torque wrench socket size matches whatever wrenches you're using, this will likely be a 1/2" socket!

Suggested Options:

AR-15 Armorer's Wrench [VITAL] [FULL GUN]

All sorts of shit on your gun requires weird wrenches to torque it down. this is not quite all-in-one, but a most-in-one solution. The primary thing that needs an odd wrench is your Castle Nut. You may be able to torque down a barrel nut with a manufacturer-provided wrench but not all manufs provide one for free. You may be able to torque down a muzzle device with other tools you have on hand but many of these wrenches include a hole for basic muzzle device torquing. The description for each wrench will list the major features it provides.

Suggested Options:

A Mallet [VITAL] [FULL GUN]

Doesn't need to be fancy. You've gotta pound some shit into place, and tap pins in as well. A normal metal hammer will be loud as fuck and might chip whatever parts you're hammering. Rubber/synthetic mallets are the way to go.

Suggested Options:

Allen Key/Wrench Set [VITAL] [FULL GUN]

Theres a lot of shit on a gun that needs an allen key, you are going to need one and might as well get a set.

Suggested Options:

A Nice Long Flathead Screwdriver [VITAL] [LOWER]

Ya gotta put the fucking pistol grip on, and a decent amount of normal flatheads just dont fit up the damn grip far enough. I'm not gonna give specific recs but make sure the screwdriver at least has 5" of shaft. NOT ALL GRIPS USE A FLATHEAD, SOME USE A HEX KEY.

Grease/Anti-Sieze/Anti-Galling Shit [SUGGESTED] [FULL GUN]

These compounds will help you put on a castle nut and barrel nut without potentially fucking up your threads. You technically can build an AR without these but fuck, you're running the risk of damaging expensive gun parts. You don't really have a good excuse not to buy it tbh, its cheap as shit.

Suggested Options:

A Punch Set [SUGGESTED] [FULL GUN]

You can probably get away with hammering on your pins directly, and using random screwdrivers if you really need a pin. But god its such a fucking pain. Get a steel set for stuff you wanna fucking Hit, and a brass set if you care about marring the surface finish or deforming anything.

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Roll Pin Starters [SUGGESTED] [FULL GUN]

Not super needed if you already have a punch set, but it makes it a lottttt easier and a lot less finnicky to start hammering in your roll pins. I've lost count of how many times ive dropped a roll pin while trying to start hammering it in.

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Breaker Bar [OPTIONAL] [FULL GUN]

You can technically get away with using a torque wrench in reverse at a higher torque setting than spec to back off the stuff that needs to get torqued down. HOWEVER, a breaker bar is far better at the task and less likely to fuck up. Grab one if you have the cash.

Suggested Options:

Center Punch [OPTIONAL] [LOWER]

Some people really wanna stake their Castle Nut properly. This does a better job than a standard steel punch.

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