I pieced together a $2000+ or more dollar build and used Aero upper and lower receiver. I read several places that Aero receivers were great and just as good as higher end receivers. The only thing is, there is significant movement between the receivers. I'm OCD and its bothering the crap out of me. I fixed the issue with the built in tensioning screw, but now my takedown pins are super tight.


Did I mess up lol?This is my first expensive build lol.

Not to play the pissing match game, but I have rifles with optics on them above $2k.  I don't give two shits about upper to lower play.

you are fine thats what the screw is for

You’re fine. However if it bothers you to the point where you want to change receivers then check out SOLGW by far the tightest most snug fit I’ve ever had

a. No you did not.
b. The adjustment screw with nylon tip is there for OCD people as yourself and no other reason.
3. I hope you got up to that dollar amount because of optics/illumination.

I haven't owned any Aero stuff but looking at the fit and finish on the receiver sets I've seen o think that's as good as it gets when saving the budget towards other parts.

You can look into options to tighten the play up but as far as changing it out to something tighter I feel unless the company has some sort of design for this issue it's a roll of the dice. Any brand cheap or high end can be tight or have play. I personally learned it doesn't matter but to each it's own.

$2000 can add up quickly in builds I've learned when you start to get pieces one at a time.

Hodge barrel, LMT enhanced bolt, colt Bolt carrier, Geissele trigger, Geissele handguard, Radian talon selector and radian charging handle.


Yeah its over $2000 before the vortex razor and badger condition one i have on the way.

Total build is like 4 grand ish? Yeah..... I know. My wallet felt that

Sounds like a nice rifle, what bbl length? Most of my builds use Aero receivers, they are great. Shoot the rifle and you will probably forget about the upper/lower wiggle.

Buy once, cry once (or in my case, 4 times..)

I've built 4 nice SBR's. With "mother may I" tax stamps just to build them, plus a can + tax stamp.. they're all over $4k/ea. Oh well, I don't regret doing them one bit.

Took me the past 7 years to get them all done.

Enjoy the butt hurt!

Does sound nice!

Right I don't even add up my builds anymore I may not drop it all at once but by the time I count everything from parts, sling, light, and optic I'm willing to bet I have a few 3k-4k setups. I don't even want to do the math. I could easily have a few scars and sr25s if I saved the money over building piece by piece

Yeah I love it. Its a 14.5 pin and weld. Law tactical folder.

I've been buying parts for a year.

Yeah, but half the fun for me is the build. I wrench on everything... find it extremely therapeutic.

No regrets.. my problem is I spreadsheet every gun build. OCD as fuck!

Never had an issue with Aero receivers and my most expensive rifle has an Aero upper. It's fine.

These are the best "solution" that I've found...order an assortment and simply install the largest that will fit...totally eliminates any play:

https://triggershims.com/ar_15_shims.php#S23

You did nothing wrong, Aero Precision receivers are nice. On the tensioning screw to adjust for that upper, the trick is to get the Nylon tipped screw to put just barely enough tension on the rear take down pin to take the wobble out or at least most of it if it bothers you without putting so much pressure on it that you can't move the take down pin. I usually adjust mine before installing the grip to access that screw from the bottom and keep turning it in small increments until it is difficult to move the take down pin. Then I know I'm close and I back it off just a hair so everything works fine. Some grips, like B5 Systems, have a second hole in them to allow you to adjust that tensioning screw even with the grip on which makes it nice. But if you have something like a standard A2 grip the method I described works well. Nice build and hope you enjoy it :)

I've gotten plenty joy out of building and shooting them I'm not complaining. I could be blowing money on other things I don't need and have nothing to show for it.

Wow so much good information and advice in this thread. Thank you everyone

Aero lowers have tension screws, if you beleive in that sort of thing.

My most recent AR has an aero upper and lower and is completely wobble free without ever touching the tension screw. I guess it's just luck of the draw. Try backing the screw out just a touch and see if it frees up the pin. Find a happy medium between the two and call it good. Wobble is annoying, but hurts nothing.

Yeah I am using it now. Do you not use them?

if it was me personally I would try and pick up a nicer receiver set and set aside the Aero for another build.  Aero's are great, but if you're OCD and have spent for top tier parts on everything else, and the funds are there for another receiver set, I'd look at picking up something that fits together nicer.  I like my receivers to stick together w/o pins in them.

will you get any performance difference?  probably not.

Yeah.  For my first build I tried to cut costs where I could without sacrificing what I wanted in the build (mainly looking for deals and such, even if it made getting a part take a lot longer), but even then, they added up very quickly, especially since I was using quality parts, including Geissele, Daniel Defense, LMT (including an e-bolt), and such.  Small parts can even add up quickly, since the neater ones, feature-wise, tend to be pricey compared to standard parts.  On the other hand, by spreading out the costs over the span of more than a year, it made it much easier to afford.  I also had a bit of custom gunsmithing work done, which added to the cost (having a stand-alone bayonet lug made out of a FSB and having the gas block journal reduced to 0.625", since DD's lightweight profile barrels switched to 0.75" journals a few years ago for some reason).  

Cost was around $2,200, not including accessories (once I get the optic, mount, light and such that I want for the build, it'll probably be approaching $4k); that also does not include the Geissele SSA-E, since I got it through Cola Warrior; the value of that added would make the rifle cost over $2,400.  Pretty much into the lower end of the price range for a KAC SR-15 E3 Mod 2.  Unlike that rifle, though, this one comes the way I wanted it, which is the nice thing about builds.  The rifles are truly customized to what the user desires.

I did use Aero Precision for the upper, lower, receiver extension, and some small parts, and I'm happy with what I got.  There is a tiny amount of receiver play, but not enough to bother me; I'm sure the tension screw could fix that.  I went with them partly because they were a bit nicer than the cheapest stuff without adding a bunch of extra cost for just a name and maybe minimal improvement.  The main reason, though, was because they had a short-throw selector lower as well as a forged flat-top upper with no forward assist (I didn't want one) and with an ejection port cover, which is not very common for whatever reason.  I actually don't recall seeing any options other than Aero for that when I was shopping for the upper.

<this.

Just loosen the tensioning screws a quarter turn. The entire industry has gone full retard trying to make the upper/lower fit so tight now you need a hammer to take them apart. This is not progress.

I used an Aero upper on an old Runner Runner lower on my Texas rifle and it was a super tight fit. I had to use a punch to get the pushpins out. I think it's just luck of the draw sometimes.

OTH, a recent SOLGW pistol project is a little loosey-goosey in regards to upper/lower fit, but it doesn't bother me.

I wouldn't worry about it OP. It does sound like a nice rifle.

OP, can you post some pics?  Curious now what your rifle looks like.

Build is fine OP.  What LPK did you use?

Pretty Gucci....Which trigger? Hopefully the Hi Speed??
LMT Bolt....What is enhanced? Aren’t the std bolts good?
Hodge barrel....How does it shoot? Larue’s shoot. Wilson’s shoot. Shilen’s shoot, Kreiger, Brux, etc....Never heard of Hodge.

I’m just asking to learn... mine is old school. Brownell’s BCG, ALG Forearm, PRS Stock, Triggertech Diamond, Wilson barrel, Aero M4E1 upper & lower set....but I think I’m under $1500 before optic.

Aero lowers work just as good as all my other lowers. Some have cooler roll marks, but that's about it.

I don’t care how much you spend.  Some wobble,  aome don’t. Just the nature with ARs.

For a 2k build I would have used Mega made receivers (Zev, SOLGW, Triarc, Hodge, etc.)

Very common and necessary to avoid tolerance stacking where the lower wont fit an upper.

The money should be in the barrels and bcg, and perhaps a 1:1 for reciever set to barrel price.

I actually prefer Aero M4E1 receivers no matter the cost. As others stated, try the tension screw next to the grip screw.

Lmao, all my builds have started on spreadsheets, and I have spreadsheets going on all my planned builds to keep up with parts i need including prices...fuck me, thats a good way to see the hurt coming to my wallet, LOL...

Nope, I've never cared that much about receiver slop. Plus I don't want to put upward tension on the upper that has the BCG riding it it over the hammer etc. and into the receiver extension and cause any unatural wear.

Aero is my go to for builds. Mainly because the roll mark doesn’t look like a gay cornucopia.

I don’t know if they do it anymore but they used to sell matches recievers.

They were most likely just test fits until they found a nice match but damn were they tight.


My best fit ever was a rock river. Couldnt close it on a piece of paper it was so tight. But alas RR decided to make backdoor deals so I won’t be buying from them again.

They were overpriced anyway

Put a loaded mag in, does it still wobble??

Slightly loosen tension screw and lube and work your take down pins.  The parts are new.  Once some of the coating wears off then re-tighten tension screw.

Which Aero lower/upper did you buy?

Aero is a great mid-level brand, I would argue the 'best' mid-level brand. I really like Aero products... YMMV
I have an Aero m4e1 upper/lower and it fits tight like a glove. It is rock solid, and I didn't have to use the tension screw at all.

I would try messing with the tension screw - try making it tighter, and then try it loose with no tension... perhaps if it is too tight, the upper is "rocking" on this pin?

However, it really doesn't matter... unless this is a heavy-use competition gun, I wouldn't worry about it and have seen many ARs with a little bit of play between upper/lower. That is why they started making the lowers with the tension screws to begin with.

I found my $500 AR at 200 yds, the scope POI would shift a bit as you described as I leaned on the rifle.
I just put a small o-ring from Home Despot plumbing department that fits snugly around the front takedown post. Make sure it does not interfere with bullet feed from magazine. It does not shift at all. Buy a box of 10 or so as you will crush it pretty good. Like $3.50

No one has suggested an accuwedge yet?

Y'all are slacking!!

I pieced together one as well.

Except, I used MEGA lower and MEGA upper I found
with MEGA 14.5 barrel.

Yours should do very well

ETA" cost was just under $2k (w/o optic) if factor pre-Covid pricing.
I gathered those parts 2-3 years ago. Everything is top shelf on it.

I have a few factory ARs (and even some parts guns using known upper / lower from the same manufacturer) with no play between the uppers and a tight fit for the pins -  I think this is par for the course, really cant have one wihtout the other and some are extreme so you need something to get the pin started.  I am OCD as well so if I have an AR with play, I take a 10 cent rubber "o-ring" used for propane tanks and available at any hardware store and put it over the front lug on the upper and snug it up against the receiver before assembly.  Cheap easy fix.  Your welcome.

You can get some slightly under or oversized  takedown/pivot pins. I want to say I got mine from JP rifles. They seemed to snug up my one of my builds that had some play in it. It’s funny when you finish a build that feels just right for the application you’re intending only to realize that your build is several thousand dollars more than what you thought it would be.

You are going to spend a lot of money to consistently get a pair of matched receiver halves that don't wobble.  Like, double or more, if you can even find them in stock.  

It doesn't hurt anything; don't worry about it.

That's funny, I built two poverty pony guns using Anderson uppers as well. I need a punch almost every time to work the rear takedown pin, solid as a rock together

At 2k I would pony up a few hundred more and get a top tier gun like a kac or something.