Aero Precision AR-15 Standard Lower Parts Kit

Manufactured by Aero Precision
SKU: APRH100029
MPN: APRH100029
Manufactured by Aero Precision
18 Reviews

In Stock

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The Aero Precision Lower Parts Kit includes everything you need to assemble a stripped lower receiver. This AR lower parts kit with MIL-SPEC dimensions and coatings ensure the highest quality and correct component interface.

Kit includes:
  • Takedown/pivot spring
  • Takedown/pivot detent
  • Trigger/hammer pin
  • Takedown pin
  • Pivot pin
  • Bolt catch
  • Bolt catch spring
  • Bolt catch buffer
  • Bolt catch roll pin
  • Safety selector
  • Safety selector spring
  • Safety selector detent
  • Buffer retainer
  • Buffer retainer spring
  • Trigger guard
  • Trigger guard roll pin
  • A2 pistol grip
  • Pistol grip screw
  • Pistol grip lock washer
  • Trigger spring
  • Hammer spring
  • Disconnector spring
  • Magazine catch body
  • Magazine catch spring
  • Magazine catch button
  • Hammer
  • Trigger
  • Disconnector

Aero Precision takes some of the most state of the art manufacturing techniques and equipment derived from their work in the aerospace industry and applies it to their products in the firearms industry. They have utilized their knowledge from years of building aircraft components to design and engineer AR-15 handguards, receiver sets, scope mounts, and more. They treat every product as if it were a precision flying machine and adhere to strict quality standards to ensure law enforcement, military, and civilian customers receive a product they can rely on.
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BrandAero Precision
Manufacturer.Aero Precision
Weight7.5 Oz

WARNING: This Product can expose you to chemicals which is known to state of California to cause Cancer and Reproductive Harm. For more information, see


by -

Fit my Anderson lower like a champ. No filing necessary. Works great out of the box. Will buy again.

Surprisingly decent trigger

by -

Didn't think the trigger would be any good. I've had a couple rifles, a spikes and a DDM4v5 LW, both purchased new as complete rifles straight from the manufacturers. The stock GI triggers sucked, even more on the Daniel Defense than on the Spikes. Lots of grittyness and creep, but I was surprised to find that this GI trigger that comes with this LPK is actually pretty crisp, with barely any creep or takeup. No grittyness, although it is a bit heavy of a pull which is to be expected.
<br>It's definitely not a Geissele or Timney, but it's definitely not bad for a basic GI trigger out of an LPK.

parts fell out of shipping box.


well during shipping the bag in the box busted open. lost some small parts smh. not to happy about that at all
<br>From PA: You didn't leave your contact info. Give us a holler and we will square you away.

Save your money


This is without a doubt the worst looking lower parts kit I have ever seen. I've used rock river psa and cmmg among others in the past and up til now I thought the psa was the worst (rock river the best). I have a job that requires me to mic parts figure grind angles and back cut bore angles (my experience reference). The 1st thing I did was pull out the fire control group and that's when I saw the casting issues. large voids in the grind surfaces(air pockets formed during poor casting) which are easily visible in low light with the naked eye at distance. The next thing I noticed were the grind angles on the sear interface which are not flat or cut with any precision at all look like my 6 year old ground them. I'm a fan of aero's upper and lowers and I'm also a primary arms fan and order from them when ever possible. That said if I were Aero I would be ashamed to put my name on these. PA should pull them send em back.

Great Kit


I have purchased a couple of these. Everything is satisfactory about this lower parts kit. The trigger is much better smoother crisp and maybe a bit lighter overall than the triggers in 3 Palmetto kits I have assembled into rifles.

Good lpk


I installed this kit in my Anderson lower everything fit nice and easy and has a crisp clean trigger pull. No complaints on my end

Bent bolt catch


I ordered 2 of these because they were out of spikes lower kits. 1 had a bent bolt catch. It was so bad the catch ground the finish off my lower. I didn't notice until it was installed. I've built 9 lowers and this was the worst parts kit I've used. Trigger is horrible compared to spikes and palmetto lower parts kits.

No problems here.


Good quality LPK for the price. Trigger is as expected for the price though.

Very nice set!


Everything fit perfectly into my lower receiver! No issues at all and will definitely recommend!

Very pleased


Excellent customer service from Primary Arms who responded to a question with both a phone call and an email. The LPK dropped right in and operates perfectly.

Unimpressed and rear Take-Down pin is malfunctioning


Rear Take-down pin appears to be milled to deep in the ends. The Detent falls to deep into the slot and will not allow the rear pin to move at all. Rendering my lower as a USELESS paper-weight until I can get a new Take-down pin assembly.<br>Trigger is also very unimpressive. I bought an assembled Aero Lower and loved the trigger. This one is no where near the same. Lots of Creep.

There is a difference.


This is only my second build. I used an Anderson lpk on my first and wanted to try other manufacturer’s lpk to have something to compare it with. The Anderson lpk with the stainless trigger group, I thought was pretty decent. After having installed this Aero lpk, I can feel a difference. All the actions are so much smoother. Take down pins, safety selector, trigger group all function smoothly without any grittiness. Don’t get me wrong. I still think the Anderson lpk is good. But as I said now I have something to compare it to and will probably use the Aero as a baseline.


by -

worked out great.

Affordable, reliable.

by -

Works very well, fit and finish are top notch. No issues installing into my Aero Lower. Will buy again, recommended.

Not impressed with this parts kit at all.


The hammer would not release to reset when first installed. I could see from the marks left that the faces were not ground parallel to each other, the disconnector was contacting on one edge only and the mating surface on the hammer wasn't ground at all, it still had a melonite like finish on it, which is why it would not release. Being I had purchased this set some time ago I tried burnishing the mating surface on the hammer with some stones, which worked and the trigger would then reset and release the hammer, but then the hammer would drop all the way forward without any trigger press. (In other words, it would fire from reset). I have no interest in something as unsafe as this being in my weapon, so out it came and the hammer and disconnector went straight into the trash can. Overall, this kit has several issues with quality and although I've never had an issue with an Aero Precision part, ever, I certain can't recommend this kit for anything other than spare parts.

Rough, low quality...

by -

I've built and serviced quite a few AR15s and I have to say, this was probably the first time I've had any issues with any lower parts kit. Dare I say that this lower parts kit is cheap...compared to other brands, this kit seems to be sub-standard in quality. The Aero Precision safety selector felt like a floppy fish with the included hardware, no matter what, I could not get it to have a positive feel / click. The trigger was not much better. Luckily, I have some spare lower parts and used a Seekins ambi-selector which fit perfect. I would suggest spending a couple of bucks extra in purchasing a high quality lower parts kit. I will stick to Spike's and CMMG for now on...

Decent for the money

by -

Not the best, but certainly not the worst. I usually keep a few of these on hand just in case of replacement parts or springs, but overall they function relative to their production. It works, but not the best on the market.

Just don’t.

by -

This is absolutely the roughest lower build kit I have ever used.
<br>The bolt catch is so out of spec that I can’t believe it made it past any measure of Q.C.
<br>The face of the bolt catch is smooth and you will not be able to use a BAD Lever on it.
<br>Very sloppy workmanship, which is a shame since I am building an Aero Precision upper and lower kit....kinda makes me wonder if the same standards were used for the milling process of the receiver set?