Building ARs is FUN! (for the new folks)

Everybody and their sister's brother's uncle already owns an AR-15. Everybody and their uncle has put an AR-15 together from parts.

Or at least that is what I assumed.

I was talking to somebody the other day and was shocked by something that should NOT have surprised me. But it did anyway. So many people have become new firearms owners over the past couple of years. Things that I take for granted are brand new to a lot of people. That includes a lot of new forum members. The other day I was at a match of all places, and someone told me that they were thinking about buying an AR-15 but they didn't know where to start. They also wanted certain features that apparently didn't come on an off the shelf AR-15.

There I stood, judgmental and incredulous. "Just put one together" says I. To which the person replied "I don't know how that works". And they were ashamed to admit it. Then it hit me. In my circle of people, everybody owns a whole bunch of different guns, is an old gray haired (usually fat) dude like me that knows exactly what they want and how to get it. I'd been making assumptions about what people know.

At that point I felt very ashamed for making them feel ashamed. Not a very nice way to bring people into the fold. Naturally I am helping this person figure things out.

It then occurred to me that maybe I should make a build thread somewhere out in the front part of the forum. Even though it'll be really old hat for a lot of folks. But for a few of you out there...this is new and exciting. (Though let's be honest. Putting together a new firearm is always a kick for the seasoned enthusiast too.)

Maybe this will inspire someone that just bought their first ever firearm, say a handgun for concealed carry, to build an AR-15. The old saying is true. "When you need a rifle, nothing else will do".

I am a fan of Aero Precision. Not sponsored by them so I don't have any skin in that game. But they do make the best bang for the buck when it comes to AR15s in my humble opinion. This will be a show and tell thread, of a sort. Not a "how to" per se but may it'll encourage some folks to build one. Or two. Whatever.

First thing I did was reach out to @DavesBuddysNeighbor. He's an FFL that is an Aero Precision dealer. He's a good dude. I highly recommend him. He did not ask me to make this thread or give me anything for it. I'm doing this cause I want to and...well cause I can.

(Lots of dudes on here know more than me when it comes to this platform. Ain't trying to say I'm any sort of expert.)

One can just go to the Aero Precision website and figure out maybe what sort of rifle/pistol they want. https://www.aeroprecisionusa.com/. Clay aka Davesbuddythisnameiswaytoolong can make some suggestions and so forth. He might have some stuff on hand. Might have to order it, but it'll get around pretty quick. Shoot him a PM or whatever and I'm sure he will get ya squared away.

I went with a 10.5" pistol build that I will probably make into an SBR at some point down the road. Build list is as follows:

Aero Precision M4E1 Stripped Lower in Flat Dark Earth
Aero Precision M4E1 Complete Upper in Flat Dark Earth
Aero Precision Lower Parts Kit
Aero Precision Enhanced Bolt Carrier Group (nickel boron finish)
Aero Precision Enhanced buffer tube assembly
A random charging handle that was laying around (to be replaced by a Geissele soon)
SBA3 pistol brace (temporary until I SBR it or whatever)
Umbrella Corporation grip in Flat Dark Earth
LaRue MBT 2 Stage trigger (flat)
Aimpoint Comp ML2 in a LaRue mount

I'll continue to update this as I make progress.

Here's the big 'ol pile of parts, ready to be assembled:



No I did not bother to clean off my bench.

Do assemble

Time for assembly.

First I got most of my pieces/parts out, of course. I always start with the lower and put the bolt catch and magazine release in first. Then more on to the trigger.



And I love the LaRue triggers. They are really a great value. The two stage ones are my pick. Either the curved or flat, both are great. See that short little silver pin on the far right? That's the slave pin. It makes life MUCH easier if you don't have a drop in trigger or a LaRue that doesn't need one. A mil-spec trigger is just fine for starting out, and you'll want a slave pin to hold some things together.

The Aero M4E1 is probably my favorite lower to use because it uses a screw for the bolt catch instead of a roll pin. Much more convenient-er.


Don’t be intimidated!

There are YouTube videos to walk you through putting it together. Or better yet, if you aren’t too far from central NC, I might be able to put it together for you. Lots of nice folks on this forum that are willing to help out as well. Asking around will more than likely get good results.

The rest of it is pretty straightforward. This ain’t an instructional thread by any means. The point is to show that anybody can take the plunge and build the rifle or pistol you really want.

This would look better with a flat dark earth brace and I’ll get around to that eventually. For now this ain’t half bad. Also stuck a pair of Troy flip up sights on there for fun.

Hope this inspires a few to go ahead and give it a whirl.

Studentofthegun said:

Also stuck a pair of Troy flip up sights on there for fun

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Something looks funny about those to me.


Nice thread. 👍

Frank C Lyons said:

Something looks funny about those to me.


Nice thread. 👍

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ROFL that's what I get for doing this while I'm really tired.

And also with one eye on the television. That'll teach me.

Edit: fixed!

Studentofthegun said:

There are YouTube videos to walk you through putting it together. Or better yet, if you aren’t too far from central NC, I might be able to put it together for you. Lots of nice folks on this forum that are willing to help out as well. Asking around will more than likely get good results.

View attachment 444648

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I showed a guy I use to work with how to assemble a lower receiver on the tailgate of his truck in the parking lot of a gas station. I made sure I didn't launch any detent pins.[emoji1787][emoji1787][emoji1787][emoji1787]

Sent from my SM-J320V using Tapatalk

The first AR i ever owned i built

I just ordered another parts kit to build another one because i have an empty lower sitting around and that just wont do.

that reminds me I need to order another lower so i can always have an empty one...just in case...

I've never owned a factory AR!

Super fun to build your own. I will say a little experience shooting them is helpful, just to get an idea of what you want.
That is what is so cool about AR's: the modularity and flexibility. You can do so many different things/styles. From precision bench gun to tiny PDW. Even using the same lower, with a couple uppers. Even different calibers. The sky is the limit. Try that with an AK.

Once you put a couple together you start to really appreciate the sheer genius behind the design.

I hate building them. I am Frankie Five Thumbs. I gladly pay someone else to assemble. I do wish I enjoyed it.

Chuckman said:

I hate building them. I am Frankie Five Thumbs. I gladly pay someone else to assemble. I do wish I enjoyed it.

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Pay people? Heck with that. Trade it out homie. Teach me how to stop someone from bleeding out or something and I'll build whatever the heck you want.

I was just talking with @JRHorne about this last night. I purchased my first gun in 2019, first poverty pony in 2020. Since then with his help i have grown to like and appreciate better more gucci items and now i can assemble my own ar15s thanks to him showing me a thing or 5. Its really enjoyable and a thrill to piece together your build and build it yourself!!! Just put together my mars-l lower last night!!

Yeah man it is amazing how many of my “gun friends” don’t know how to do basic maintenance let alone swapping parts or building one, personally I learned 50% of what I know by watching YouTube videos on how to do “something” without the proper tool/s, do this day I still use a razor blade to install the front spring & detent when installing the front take down pin.

I’ve helped a couple of friends replace triggers, safety selectors gas blocks etc but just walked them through the process, I have them watch a “how too” video and then let them have at it with me watching, two of those guys are now in the process of gathering parts & tools so they can built their own, my only real advice is “use good parts and avoid the gun show special crap”, one guy is stuffing mid/upper components (BCM BCG, Ballistic advantage barrel, CMMG build kit etc) into an Anderson receiver set and he’ll have a hell of a nice rifle for less than he paid for his Springfield Saint and he’s stoked about it lol

Been issued many by Uncle Sam and but never bought my own complete AR. Built my first one back in 87' when there were few pickings to choose from. Have built over 24 semi auto ARs. I do rebuild hundreds of M4s/M16s for Uncle now however. One I carried in Afghanistan from 17'-22'. I've replaced 3 barrels on it that were shot out. Notice Gessiele SSF trigger and auto sear above between trigger/hammer. Picture taken during deep cleaning.


CD

Nice build!

Studentofthegun said:

Time for assembly.

First I got most of my pieces/parts out, of course. I always start with the lower and put the bolt catch and magazine release in first. Then more on to the trigger.

View attachment 444637

And I love the LaRue triggers. They are really a great value. The two stage ones are my pick. Either the curved or flat, both are great. See that short little silver pin on the far right? That's the slave pin. It makes life MUCH easier if you don't have a drop in trigger or a LaRue that doesn't need one. A mil-spec trigger is just fine for starting out, and you'll want a slave pin to hold some things together.

The Aero M4E1 is probably my favorite lower to use because it uses a screw for the bolt catch instead of a roll pin. Much more convenient-er.
View attachment 444640

Don’t be intimidated!

There are YouTube videos to walk you through putting it together. Or better yet, if you aren’t too far from central NC, I might be able to put it together for you. Lots of nice folks on this forum that are willing to help out as well. Asking around will more than likely get good results.

The rest of it is pretty straightforward. This ain’t an instructional thread by any means. The point is to show that anybody can take the plunge and build the rifle or pistol you really want.

This would look better with a flat dark earth brace and I’ll get around to that eventually. For now this ain’t half bad. Also stuck a pair of Troy flip up sights on there for fun.

Hope this inspires a few to go ahead and give it a whirl.

View attachment 444648

Click to expand...

I did a version of this thread here:


…mainly to convince people it’s not that difficult. 😁

(Walked my then-12yo son through it, and documented with some pics)

The first lower I assembled over a decade ago, I could not for the life of me get the dang pivot detent in. Thankfully a fellow member of the original Carolina site (can’t remember his name anymore) allowed me to come to his office in CLT and showed me how he does it. Of course it took him maybe a minute and we chatted for a few.

Now I can do it easily after having built dozens of lowers but we do sometimes forget how intimidating building your first gun of any type can be. I went through this with a P80 last year but thankfully found all of the info I needed on forums and YouTube.

For the front pivot dent pin, I insert from the left a allen key (sized to fit) and push across to hold the dent pin/spring in. Then push in the pivot pin from the right and once pin is in rotate to have dent snap into recess. Allen key acts as a slave pin.

CD

Combat Diver said:

For the front pivot dent pin, I insert from the left a allen key (sized to fit) and push across to hold the dent pin/spring in. Then push in the pivot pin from the right and once pin is in rotate to have dent snap into recess. Allen key acts as a slave pin.

CD

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Cotter pin and a punch (or anything that fits through the hole in the cotter pin) make a real quick job of it.

Very nice!

For the time being, I'd NOT "stock" it and (attempt to ) register it. The retards at ATF may very well claim that it was a SBR before you put a stock on it, as they're claiming now on Suppressors. ("if you have a bar of aluminum, you have a suppressor...and you can't Form 1 a n illegal suppressor")

bought my first AR and customized it, then bought a stripped lower. then i bought another AR and swapped all the parts around with the stripped lower
i've been turning spare parts into new guns ever since

I was one of those people for the longest time. I bought an AR-10 (ok, an lr308 but I call them all AR10s as do almost everyone) over 10 years ago and knew very little about them. My first AR-15 wasn't until two years ago at the beginning of the plandemic. Bought a M&P sport like half of America did. (Yes that's melodramatic but FG&G was selling literal truck loads of them every day.) Then, I started wanting a more specific AR-10. (I love and reload for 308.) So I needed to build it. That started the whole journey. I spent so much time researching and talking to friends online. If I'd had one good friend just sit with me and walk me through everything it would have been so much nicer and easier. Sadly I have no such friends in real life.

There are a few things I'll add to this thread that should be discussed. First: TOOLS. Some tools are just plain essential, in my opinion: a vice, armorer's wrench, upper and lower blocks for use with vice, torque wrench, set of punches, hammer of course, and a good set of Allen wrenches. For the upper I have a block from Odin works. It's damn awesome as one side is for an AR-10 and flip it over for a 15. It's way better than the vice block that you put the upper into especially since I've built as many 10s as I have 15s. For the lower I just use one of those magazines type blocks. One side acts like a magazine and the other goes into the vice. SECOND: is parts compatibility. Some things, namely uppers and handguard/barrel nuts are proprietary and must be used together. There is no easy list, you just have to investigate. It's usually best to buy the upper and handguard from the same manufacturer and "probably" the lower too. As has been said, Aero is the king of high quality, affordable parts. However, they have a few different types of uppers and handguards that must be used together.

That's just some basics, there's a lot more to it. I don't think anyone needs to walk through putting it all together as there are many YouTube vids to watch for that. I think a good thing to add would be a full parts list of what you'll have to buy in order to build one.

Personally, for me, I like building because I can choose quality parts, namely the trigger and barrel. They make such a MASSIVE difference. Just the barrel and trigger for my latest build cost as much as the entire M&P I bought a few years ago. I also take a long time with some builds, buying a part here or there when good deals become available. I don't just sit down and buy everything at once.

I'd suggest putting all these helpful tips together and make one pinned thread. That would have been SOOOO nice to have when I started my journey.

For the beginner.

An AR what's that? Assembled a few here and there, into retro builds mainly picked up a few Sendra lowers decades ago (cheap) When Rock Island Armory got sued by Colt
Colt parts were everywhere back then, chrome bolt carrier groups, etc. like the XM177 clones, CAR's, etc. They are easy to assemble, the right tools help. Just don't like it when those detents go flying.

-Snoopz

I see it like changing the oil in your car yourself. You may pay about the same getting the filter and oil you want, but that same cost gets you a better quality product. I've built 3 budget ARs and still have 2 of them. Just found a lower parts kit yesterday so now I need to start the journey over again. I am a destroyer of everything so if I can do it anyone can.

I mentioned this one little thing to another member the other day, get a decent vise and mount it to your bench. A cheap vise clamped to a table is a disaster, it makes the process much harder. As usual, I go overboard, but get an old, maybe rusty but not broken, heavy vise from craigslist, clean it up, mount it right, and use it forever. You’ll find a lot of uses for it.

CD

Thanks for the post! Built an upper on a preassembled lower last year, and just built a lower with a preassembled upper this year, lol. Definitely more intimidating than it really is. But my question, that ALWAYS gets differing opinions...is how important is it to actually buy/use headpsace gauges?

Chris24 said:

Thanks for the post! Built an upper on a preassembled lower last year, and just built a lower with a preassembled upper this year, lol. Definitely more intimidating than it really is. But my question, that ALWAYS gets differing opinions...is how important is it to actually buy/use headpsace gauges?

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If you're getting a preassembled upper (or complete gun), I wouldn't worry about headspacing. I have yet to find one that's out of spec from any name brand manufacturer. I'm not saying it never happens, but I think the risk is very low.

However, I'd still recommend you have a set of gauges and learn to use them properly. It's an important tool in your toolbox, especially if down the road you pick up an older AR with unknown history (possible abuse or bubbasmithing). But it's not critical to buy them right away when first starting out.

shackleford said:

If you're getting a preassembled upper (or complete gun), I wouldn't worry about headspacing. I have yet to find one that's out of spec from any name brand manufacturer. I'm not saying it never happens, but I think the risk is very low.

However, I'd still recommend you have a set of gauges and learn to use them properly. It's an important tool in your toolbox, especially if down the road you pick up an older AR with unknown history (possible abuse or bubbasmithing). But it's not critical to buy them right away when first starting out.

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when i first started building uppers, people looked at me like i was insane when i wanted my stuff headspaced. apparently the spec is loose enough and every manufacturer good enough that out of spec just plain doesn't happen with ARs....
I got my own go/nogo gauges.

JimB said:

I mentioned this one little thing to another member the other day, get a decent vise and mount it to your bench. A cheap vise clamped to a table is a disaster, it makes the process much harder. As usual, I go overboard, but get an old, maybe rusty but not broken, heavy vise from craigslist, clean it up, mount it right, and use it forever. You’ll find a lot of uses for it.

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Exactly a good vise, have a 6" very Heavy Machinist Vise, is it over kill? Probably.. It works and works great.
Have an AR Combo Wrench thats great, problem is the Guy who used to make them, shop burned down
decades ago. Great Tool, built like a tank.
Good tools will last a lifetime if taken care of.

-Snoopz

The proper split pin punches are very important to protect your guns finish from damage. They have a center bump on the face of the punch that keeps it from slipping off the pin. Painters tape is helpful too. My first AR in 300 blkout was assembled by professionals using Seekins and Wilson parts but I’ve since put 3 pcc lowers and 4 pcc uppers together. Like the pccs better than my rifle.

some punches

Bringing this thread back since I keep referring to it myself. I picked up an Aero M4E1 and lower parts kit today starting my first build up. This, after just 2 months ago purchasing my first AR, an off the shelf PSA, and promptly modding it to make it what I then figuring out I really wanted.
Not sure what direction I’ll go with this build yet, but it’s a start.
Good info here! Thanks!

SurfcasterPE said:

Bringing this thread back since I keep referring to it myself. I picked up an Aero M4E1 and lower parts kit today starting my first build up. This, after just 2 months ago purchasing my first AR, an off the shelf PSA, and promptly modding it to make it what I then figuring out I really wanted.
Not sure what direction I’ll go with this build yet, but it’s a start.
Good info here! Thanks!

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As someone that has done this a few times, go ahead and get the matching upper and handguard. The uppers are everywhere, on sale often. After that, mix and match as you please. Though, go ahead and get a good BCG. Toolcraft seems to be really good with some amazing coatings for not a ton of money, also on sale often. ar15discounts.com is your friend, sign up for their email notifications and kiss your credit card goodbye.

SurfcasterPE said:

Bringing this thread back since I keep referring to it myself. I picked up an Aero M4E1 and lower parts kit today starting my first build up. This, after just 2 months ago purchasing my first AR, an off the shelf PSA, and promptly modding it to make it what I then figuring out I really wanted.
Not sure what direction I’ll go with this build yet, but it’s a start.
Good info here! Thanks!

Click to expand...

congrats and good luck!

I found out that one of the young ladies who works for me is married to a Marine. and that Marine has no rifle. every few weeks i ask "hey, does your 'Marine' have a rifle yet?" they're always working on something else, so i remind her of things like "the motto is NOT 'every Marine a lawnmowerman', you know"
she insists they have a full gun safe first, and that they find a place to put a safe. for one rifle. i'm like "what good is your ONE rifle going to do for you in a safe?" she's like "but i have my 9mm..." not good enough, ma'am.

SurfcasterPE said:

Bringing this thread back since I keep referring to it myself. I picked up an Aero M4E1 and lower parts kit today starting my first build up. This, after just 2 months ago purchasing my first AR, an off the shelf PSA, and promptly modding it to make it what I then figuring out I really wanted.
Not sure what direction I’ll go with this build yet, but it’s a start.
Good info here! Thanks!

Click to expand...

Just to throw out my update- I ordered up a couple more parts over the weekend. Got the same LaRue trigger @Studentofthegun went with after researching many different options. Also ordered the matching Aero M4E1 assembled upper receiver.
Still undecided on a barrel though. Leaning towards a 20” since my use will be at a range and would like accuracy and grouping at distance over all else. Still researching that a bit. My current AR has a 16”.

I do like this trigger already. And the reading material that came with it.
I did get it installed today and like the feel. Can’t wait to try it out at the range.

Ordered up some more parts today and then I’ll be in the short roads. Ended up going with a Wilson Combat 20” 223 Wylde, Aero BCG and charging handle, DD stock, Superlative gas block. So when that stuff comes in next week I think all I’ll be lacking is a handguard and optic. I think I’m really gonna like that LaRue 2 stage and hope I made good choices on the rest.
Ar15discounts has indeed been my friend. Appreciate the tips!
Probably going to go with the Aero handguard as suggested.
Then an optic? No idea on that yet. I like the LPVO on my other AR, but I’m thinking I need something to see further. Anywho, making progress.

Short ‘rows’ is what I’ve always heard. I digress. Starting on an AR myself except going to try a .22 Solo DL-44 blaster. Been picking up bits and pieces, using a CMMG 4.5 inch .22 barrel/bcg and Canto Arms blaster parts. Don’t have a lower yet.

I’ve built a few now and what I wish I knew before going down that road is that spare parts turn into full rifles! This is my most recent one, the result of an extra trigger I had laying around…