We know what you’re thinking right now:
Why are some AR-15 lower receivers $45 and some $200+?
How do I know what’s best for me?
It’s not as intimidating as it seems, so don’t worry!
And we’ve built our fair share of ARs with a variety of lowers!
We’re going to cover the differences in manufacturing, materials, and weight to help you pick the best lower for your budget and build.
Summary of Our Top Picks
Best Budget LowerPSA lowers offer good quality at an extremely competitive price.
Editor's PickAero Precision M4E1 Stripped Lower
These are an excellent balance between quality and affordability.
Best High-End ReceiverLewis Machine & Tool AR-15 MARS-L Stripped Ambidextrous Lower
These are some of the best lowers out there.
Best Polymer LowerKE Arms KP-15 Polymer Stripped Lower Receiver
These are efficient and affordable.
Best Retro LowersThese are a must have for anyone looking to do an older clone build.
Table of Contents
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Manufacturing Processes
The overwhelming majority of lower receivers are made of aluminum.
While there are other options such as steel, titanium, and polymer, we’ll focus mostly on the three ways aluminum is made into an AR-15 receiver.
We’ll touch on polymer also, but I’ll try to be brief.
First, what are those numbers in front of the aluminum?
6061-T6 vs 7075-T6 Aluminum Receivers
There are two types of aluminum alloys that are used in making lowers. 6061-T6 and 7075-T6.
So, what’s the difference?
Simply: strength and corrosion resistance
7075-T6 is nearly twice as strong as 6061-T6. Naturally, there will be a cost difference between the two.
However, 6061 is more corrosion-resistant. But unless your receiver is bare aluminum, this part shouldn’t affect your decision too much.
When planning your build, think about how much that strength is worth to you.
Want our advice?
The difference nowadays between 7075 and 6061 is so minimal that we like the peace of mind that comes with 7075.
But if budget dictates 6061…you’re fine too.
Now onto the three ways of manufacturing a receiver.
Cast Aluminum
The casting process is very basic.
Pour the molten aluminum into a mold and once cooled, you have a lower receiver ready for final machining.
Since the aluminum is poured into the cast as a liquid the final product will have a loose crystalline structure making it the weakest form of the three types of aluminum.
It is still strong enough for the receiver to be perfectly safe without fear of malfunction.
However, it is the least desirable of the processes.
Billet Aluminum
Think of it this way, the manufacturer is Michelangelo and the billet bar stock is the marble.
The lower starts out as a block of pure aluminum that ends up on various machines that mill it into a finished product.
It is just sculpting with metal.
Because the aluminum remains solid billet lowers are stronger than cast and have a finer finish.
If you’re looking to build a “show gun” consider a billet lower!
They also have the added benefit of being easily customized by manufacturers since they start with raw aluminum.
This allows for creative changes to be made such as a skull-shaped magazine well, built-in trigger guards, and extra machining for weight savings.
Forged Aluminum
The strongest and most common of the three types.
Take some aluminum and smash it into submission.
That’s essentially what’s going on in this process.
Machines press a block of aluminum into the desired shape and then it gets machined to finish it off. The compression of the aluminum increases its strength.
This is ideal for an AR-15 you plan on using often and hauling around with you.
Ambidextrous Lowers
This is a term you’ll see pop up now and then generally on premium lowers.
If you see a brand making lowers for one price, then see some lowers for 2x or 3x the price from the same brand — chances are the expensive ones are ambi.
Ambidextrous lowers mean they have controls on both sides of the lower. How, what, and where depends on the lower.
There are no standard naming conventions for these features so you’ll often have to inspect each lower on their own to see what type they are.
The bare minimum of an ambi lower is one that has a safety selector on both sides.
A step up from those will have a magazine release AND a safety selector on both sides.
Good ones will have the mag release, the safety, and a bolt release on both sides.
The best, and in my opinion the only ones that should have the right to call themselves ambidextrous, will have the mag release, the safety, the bolt release, and a bolt catch on both sides.
Note the difference between a bolt release and a bolt catch. Often an ambi lower will let you release your bolt from both sides, but will only let you lock it back from one side. That’s useful, but it isn’t the best.
Okay, But Why?
Simple, so you can use all of the controls from both sides of the rifle.
If this is purely a range toy, then ambi really doesn’t matter. But for competition, SHTF, or home defense — I really recommend looking at ambi lowers or at least adding an ambi safety and mag to your normal lower.
You never know when you’ll be hurt, when you’ll need to switch sides when you’ll have your hands full with something or someone else.
The ability to manipulate your rifle from both sides has benefits that will only present themselves when you truly need them.
Polymer Lowers
Because of the growing popularity of polymer lowers, it’s worth talking about the pros and cons, how they are generally made, and why you might want one…or might not want one.
History Of The Polymer Lower
Surprisingly, polymer lowers really aren’t new. Colt was playing around with the design in the late ‘60s, it didn’t get past the testing phases — but they still were the first.
Polymer lowers would languish and be mostly ignored for several decades but the idea eventually came back.
Plastic is cheaper than aluminum, easy to work with, and lighter. So on paper, it makes for good material for a non-wear part like the AR-15 lower receiver.
Is It Strong Enough?
This is where we run into some issues. If you take the specs for a standard AR-15 lower and try to just make it out of polymer, you’re going to have a bad time.
Failure points like the walls around where the safety detent goes are very thin and prone to breaking.
Where the buffer tube connects to the lower is another weak point, and even the threads for the buffer tube are often a problem and wear quickly if the buffer tube is replaced more than a few times.
There are other weak points but you get the idea.
To combat this, you need a lower that is designed to be a polymer lower. You can’t just take AR-15 lower specs and switch to plastic.
Overall though, the problem with these designs is that they are just too much weakness for not enough gain.
A standard aluminum stripped lower is about 8.5 ounces, and a polymer stripped lower that is decently designed is about 5.5 ounces.
Three ounces really isn’t much weight savings and pre-covid the price wasn’t much different either, maybe a $10 difference.
The Monolithic Polymer Receiver
While the difference between a stripped Al lower and a striped poly lower might only be a few ounces, when you make the entire lower — the grip, the stock, and the receiver, out of polymer, then you can save some major weight.
A complete aluminum lower (buttstock, grip, LPK, trigger) weighs around 2.5 to 2.8 pounds. Something like the KE Arms KP-15 complete lower (buttstock, grip, LPK, trigger) weighs 1.7 pounds.
A full pound or close to it is some real weight savings.
Making the entire lower out of polymer also allows you to design it so that everything is strong enough, often stronger than an aluminum lower because it’s all one part.
There are some downsides, but there are a lot of upsides too.
Sadly, there are very few options in this category — but more on that later.
Best AR-15 Lower Receivers
Most websites are going to tell you to weigh it out and decide on your own.
Here at Pew Pew Tactical, we’d rather show you some examples and talk about them.
Frankly, we won’t cover cast lowers for two easy reasons — they’re weak and I think they’re ugly. Never have I used a cast receiver in a build and don’t think you should either.
Now let’s get on with our top picks! These are not in any set order. All of them are great, some are better than others for different reasons.
1. Palmetto State Armory
Simple forged lowers for a great price, they also offer a host of complete lower options for basically every type of AR-15 you can think of.
We’ve used and reviewed just about every AR-15 and AR-10 rifle that PSA makes and their lowers have never given us even a hint of a problem.
They even have some awesome limited edition lowers, such as their “Space Rider” stripped lower!
If there’s a current event or meme…they’ll have you covered. On the flipside…they also have “stealth” lowers that I like.
Otherwise, you can’t go wrong with their regular ones. And if you don’t feel like building the lower…check out their complete lowers.
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2. Anderson Manufacturing
Here it is, the Honda of lower receivers.
Anderson Lowers are cheap ($38 for stripped and $120 for complete), they’re forged 7075-T6, and they’re often available.
My accuracy testing lower uses the Anderson and Hiperfire trigger (Best AR-15 Triggers).
I have used their lowers on countless builds and have had zero issues with them.
If you scratch it while building, who cares? Don’t let the price fool you, these are quality basic lowers good for 90% of your potential builds as a hobby shooter. I have four of these in my safe right now just waiting to be built.
Plus there are also “stealth” versions where they don’t have the horse logo if that makes you feel better!
Prices accurate at time of writing
Prices accurate at time of writing
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3. Aero Precision
My buddies and I have built at least a dozen ARs with Aero lowers. They are all running just fine.
Aero Precision lowers ($109) are just like Anderson’s (forged 7075-T6) but their logo is better looking.
You can pair it with an Aero stripped upper receiver too which is our current favorite.
PLUS…there’s an adjustable screw for Gen 2 models that makes a tighter fit with your upper…no more rattling around!
My newest competition build utilizes an Aero FDE Gen 2 lower receiver.
Can’t wait for some future builds with more of them…my personal favorite for most builds.
Prices accurate at time of writing
Prices accurate at time of writing
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Oh…and now we have a full review on Aero’s M4E1 uppers and build kits using…you guessed it…Aero lowers.
Check out the full review of the M4E1 and all the parts used in the build.
4. F1 Firearms
This might not be the lightest set at 1.03 lbs, but it’s definitely the coolest looking.
But one thing is for sure…F1’s billet receiver set brings some style to the competition shooting game.
Of course, features like a beveled magwell and flared trigger guard do add some functionality to the cool-factor. If you are looking for something unique, this is it.
Prices accurate at time of writing
Prices accurate at time of writing
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5. Lewis Machine & Tool Company MARS-L
A truly ambi lower, the MARS-L is in our editor’s opinion the greatest lower on the market right now.
This is the same pattern of lower that New Zealand adopted as their standard issue rifle and it comes with some great features.
First and foremost, this is truly completely ambidextrous. Every control can be used from both sides, including the bolt release and stop.
They are also proprietary to the MARS-L, not just aftermarket parts slapped on a standard lower sold for 4x the price.
Downside of all of that is that these are not cheap and are often hard to find. LMT often has these back-ordered for 6 months or more at a time.
If you see one for sale, get it fast! They never stay on the shelves for long.
Prices accurate at time of writing
Prices accurate at time of writing
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6. KE Arms KP-15 Monolithic Polymer Lower
The KE Arms KP-15 was designed by KE Arms with the help of Ian McCollum and Karl Kasarda from InRangeTV based on their What Would Stoner Do 2017/2020 projects.
We used it in our very own WWSD Build.
Basically, this is a monolithic polymer lower that is designed to be such in every way.
From the ground up this is meant to be exactly what it is — strong, durable, lightweight, and reasonably priced. We enjoyed our time with it.
That said, be aware that it is a fixed stocked and the grip isn’t replaceable. So if you need those kinds of adjustments in your life, you might want to choose something else.
Otherwise, it’s a solid choice.
Prices accurate at time of writing
Prices accurate at time of writing
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7. H&R Retro Lowers
Okay, there really isn’t anything too crazy about the H&R lowers, except that they are patterned after lowers from long ago.
The AR-15 lower has changed in small ways over the years and these are throwback lowers to those bygone designs.
These are awesome for those who are looking to make a clone build like an old school M16A1, XM177, XM16E1, 635 builds, or other older AR variants.
They look good, they’re well made, and they’re fun. Plus, they are a lot cheaper than trying to source originals.
Prices accurate at time of writing
Prices accurate at time of writing
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9mm AR-15 Lowers
If we had to choose one…it’d be the PSA PX-9 lower that takes Glock mags.
See how it already looks different from regular AR-15 lowers? It’s got an ejector built in and a longer mag release.
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We cover all the differences you’ll see in pistol caliber AR lowers and the rest of our choices in Best 9mm AR Lower Receivers.
Others
But the ones I see at the gun store are not on the list?
To provide you with information and direction, the above recommendations were selected without persuasion.
There are countless other places manufacturing and machining lower receivers. As such, there are three things you should keep in mind when shopping around for them…
Material, process, and reputation of the manufacturer.
A good place to start for manufacturer reputation is with our AR-15 Buyer’s Guide. If their complete rifle is good…chances are their lowers are good too.
You can then cross-check against what is in stock at your local store so you can save on shipping.
Final Thoughts
Ultimately, you’ll get a feel for each company and find favorites, as I have.
Some people prefer different logos or roll marks, some have brand loyalty, and others only worry about the price of the lower.
There are many who choose a forged lower over the pricier billet lowers using the simple mantra “a lower, is a lower, is a lower.”
Personally, If I had to choose one lower for the rest of my builds…I’d go with the Aero. That is because Uncle Sam taught me was KISS method: Keep It Simple, Stupid.
Now that you’re armed with enough knowledge to help you sort through the haystack and narrow your search get out there and find what works for you.
Finish your lower with our Best Lower Parts Kits and also the AR-15 Resource Guide for all other parts. Or…fancy completing an 80% lower receiver? Check out our Best 80% Lowers & Jigs article.
91 Leave a Reply
I've done 3 builds so far with the PSAs (1 AR-10 and 2 AR-15s), and haven't had a single issue with any of the 3. One was a Blemished, and the only Blem I could find was a discoloration on the Magwell. Was Ceracoating it anyway, so even that wasn't an issue.
Never had a problem with an Anderson lower. Always been in spec and great quality.
I tried a polymer once... once.
Choosing from questionable manufacturers leaves you with a questionable rifle....
You need to revisit PSA lowers. They are commonly made out of spec, particularly the bolt catch location, which is farther back from the front takedown pin than it should be.
Why did you use the word STEEL in your lead
So far I love my PSA lower. But if I were to do it again, I think I would go with the Aero Precision for the simple fact of the additional screw to keep the lower and upper snug. Used a BCA upper with side charger and stainless steel barrel. I have an inexpensive rig that shoots sub par MOA.
Aero Precision is useless. They take an eternity to ship anything, lie to you about the status, and then suddenly the order is lost. Only thing they seem to do well is process refunds for the "In Stock" items they fail to ship.
I just bought 6 Aero kits. All shipped next day and I got them in 3 days. Fantastic price and quality. Built and all shoot flawlessly.
Have 2 full builds and 3 lowers from Aero. Had one issue where an order was missing an item, but they took care of it the next day. Sounds like you had one bad experience, and it’s not like you can’t buy Aero Precision stuff form other vendors.
I've built up half a dozen aero rifles with zero issues. Fantastic quality, specs, fit and finish excellent. Who did you piss off?
What do you think of zev or mega? I would love to see a review of the zev billet rifle
What all is needed to complete an LMT MARS-L lower? I'm thinking trigger group, takedown/pivot pins, buffer retainer, grip, and buffer kit. Did I miss anything?
PSA has repeatedly failed in quality control. Doesn't matter if it's a complete AR or buying a lower and building it yourself. They just can't get upper receivers & BCG's to work correctly. Marrying up the upper and lower is easy, if it doesn't go boom, or in another instance my chamber began to chip after 50 rounds, you have a giant paper weight. I know many have had great experiences and I am happy for them. As for me, I'll gladly spend more from a company who's product works right out of the box and with proper customer service.
Aluminum diecasting is not "poured" into the the mold. It's poured into a heated container then sucked into a cylinder and slammed into a mold by a piston. The mold is held closed by hydraulics and locked during the process. The pressure is immense which reduces the possibility of porosity and allows for a more uniform product. Depending on manufacturer the lower should be x-rayed to check for defects.
Great article need more! Do they make one out of a material that will last extremely long time such as in a survival situation where there is no more manufacturers to rely on? Such as maybe steel and damn the weight.
Why is there no mention of BCM? Have built two with these lowers and believe them to be TOP SHELF.
Just asking for clarity, or did I miss something?
Because they don't pay for ad space like PSA. That's why.
Thanks for reading, just to clarify we were not paid to include any lower in this review. If it's not here, we might not have had the chance to try it out yet.
Sound the Charge.
Could you do a review of The Ke arms KP9 monolithic lower? I've not heard much on it and would like to see what you guys think of it.
Once again nothing about Knight's Armament AR15, their ambidextrous lowers being top notched with an incredible match factory trigger. You seem to be definitely angry with this brand ... :D
Knights is unobtainium and out of most ppls price range. Not a brand for someone just getting into building AR’s
Ghost guns 45 Cal.
C
2A Armament & Primary Weapons Systems out of Boise, ID make an amazing upper and lowers.
My project during covid-19 shutdowns was a complete upper by Primary Weapons Systems (MK116 .223 Wylde) and 2A Armament Lower (Aethon).
Albert
now all you have to do is tell me where you can get the titanium and steel AR-15 lowers? I honestly read this whole article hoping to find out even though you said this article you were going to focus on the aluminum, I figure you might give an honorable mention, to the steel and titanium lowers, or at least where to get them or who had them.
I'm curious to find out if anyone knows which online sellers market a complete AR platform (either 15 or 10) with exception to the lower itself being an 80% rather than a stripped one?
Given that the quality is on par, I like the idea of the convenience as a buyer of not having to scour the Interweebs for all the needed components to complete a build versus just purchasing the lower apart from everything else.
So far I've only found one company who has such an offering in California named Juggernaut Tactical, but reviews on quality are mixed.
Any others out there anyone could point me to?
I built my own AR using upper by Primary Weapons Systems and lower by 2A Armament. Both built in USA and from Boise, ID.
2 more that should be on any ambi lower list; Radian AX556 and American Defense Manufacturing UIC. The ADM UIC can be had for $299, billet 7075-T6 and includes the ambi mag release and ambi bolt catch and release hardware, plus dimpled pivot and takedown pins. I'm lucky enough to live 20 minutes from ADM, so it was a no brainer when there's no shipping and they are an FFL who charge no transfer fees or background check fees on their own products, just sales tax. I'm VERY happy with mine and will likely make the ADM UIC my preferred lower from now on.
Aero lowers are great if you buy only aero parts, otherwise they are junk. They are already expensive and will cost you alot more in tge long run!
What? Couldn't be further from the truth. While I'm not a fan of the Aero lower parts kit, there is nothing proprietary about an Aero precision lower and any mil-spec part will work fine. Regardless if using the X-15 or M4E1 lowers.
The original article is a couple years old if you look back at the comments so the "prices accurate at time of writing" is technically true. I did manage to secure an Aero M4E1 stripped lower for $90 at Primary Arms a couple weeks ago. Out of stock now however. Keep looking around.
Where did you get your prices from? Because I am not seeing ANY prices that reflect your article.
Lol, never thought I'd see the Achievement Hunters on this website.
Thanks, Pew Pew Tactical. I appreciate all of your reviews.
I'm kinda new to the AR 15 world and recently did my first AR build. I used an Aero upper/lower, and a Sig Sauer Bravo3 based on your reviews — It came out awesome and shoots like a champ.
Keep up the great work!
Thanks for the guide Cameron, it's really helpful in preparing to put together a first time build. Looking at options online I came across a polymer lower, the JMT AR-15 80% Gen 2 Polymer Lower. Do you have any experience with this type of lower? If not, would you be willing to test one on a new build and give us your thoughts?
Thanks for all the great info pewpewtacital! It's all been very helpful for a noob like myself.
Jon, I used a JMT Gen 2 Lower as the start of my second build. I now have about 300 rounds down range with it and have had no issues. Seems quite solid. My problem with the Polymer lowers isn't with the lower itself so much as the cheap jigs that come with them. This was the case with both the Polymer 80 lower and the JMT lower. But both worked out fine. Go slow and get all the right tools. When drilling trigger pin holes and others plunge once and be done.
I have built half a dozen ARs om JMT polymer 80% lowers. As long as you do your part correctly they are top notch.
I really like their carbon 50 offerings.
I stumbled upon a pew pew special edition AP lower online the other day. I felt so lucky, I had to buy, now this beauty is in my lap waiting to be my first build.
I notice that many, many times when reading, and researching, and trying to comprehend some metallurgy, or engineering, gas pressures etc. when I learn a new tech term, and google to learn more, the Pew Pew site is usually in the top 6 of the search results.
Hrmmm, wonder why that is.
Thanks you guys, and of course Mr. Corley for all the good basic info to stay at least semi-cognizant of 'WTHeck' with this platform.
Thank you for your service. I am US Army Retired (31 1/2) years. I was a Cavalry Scout as well. I build my own AR 15's also. Thank you for your service to our country.
Thanks Cameron for the informational article touching on the characteristics of each manufacturing methods. Now I am able to make more educated decisions when building an AR. We appreciate you sharing your insights with us.
That funky spot on the Anderson slick uppers is a "feature" on all uppers, even my Viet Nam era upper. You just notice it because there isn't a cover there. Whoever made the forgings changed the rear to delete the forward assist, but nothing around the ejection port. On a "normal" upper, that extra lump of metal gets some machining and is somewhat hidden by the ejection port cover.
7075 80% lower for the win, for sooo many reasons.
I HAVE AND ESSENTIAL ARMS RIFLE
THAT HAS A CAST LOWER RECEIVER
FROM KROTZ SPRINGS LOUISIANA
I WAS THERE WHEN MR. VON JOHNSON STARTED MAKING THESE LOWER RECEIVER
BACK THEN THERE WAS NOT BUT A HANDFUL OF PEOPLE MAKING LOWER RECEIVER BACK IN THE EARLY 80
AND I HAVE DROPPED THIS WEAPON
AND ABUSED THESE WEAPON
TO SEE EXACTLY WHAT AND HOW IT WOULD HOLE UP
AND I ALSO HAD A COLT SPI THAT I DID THE VERY SAME TEST TO
AND THE COLT SPI ENDED UP HAVING A CRACK IN THE MAGAZINE WELL
AS FOR AS THE ESSENTIAL ARMS LOWER RECEIVER
ESPECIALLY WERE THE MAGAZINE WELL WAS
WAS THICKER IN WIDTH THAN MY COLT SPI
IF I AM WRONG PLEASE SET ME STRAIGHT
BUT THE LOWER RECEIVER HAS NO PRESSURE ON IT
UNLIKE THE UPPER RECEIVER
AM I RIGHT ARE WRONG
BECAUSE I HAVE USED THIS WEAPON
FOR EVERYTHING THAT YOU YOU COULD IMAGINE WITH ABSOLUTELY NO PROBLEM AT ALL FOR OVER THIRTY PLUS YEARS NOW
AND WHEN I WAS IN THE GUN BUSINESS
THESE LOWER WERE IN VERY HIGH DEMAND
THE DALLAS TEXAS SWAT TEAM
ACTUALLY STARTED USING THESE LOWER RECEIVER ESPECIALLY WITH THE 20 ROUND MAGAZINE OVER THE COLT LOWER RECEIVER
BECAUSE WHEN IN TRAINING
AND THE OFFICER HAD TO DROP TO THE GROUND IN A HURRY
AND THEN 20 ROUND MAGAZINE WOULD HIT SOMETHING HARD
LIKE CONCRETE OR A ROCK OR ANYTHING HARD
THE COLT LOWER RECEIVER WERE CRACKING IN THE MAGAZINE WELL
CAUSEING SEVERE PROBLEMS
MR. VON JOHNSON OF ESSENTIAL ARMS RETRIED BECAUSE OF MEDICAL PROBLEMS
AND THERE WAS NO ONE WHO WANTED TO CONTINUE WITH THE BUSINESS
I KNOW IN THIS ARTICLE ABOUT LOWER RECEIVER
IT IS SAID CAST TO BE THE WEAKEST OF THE THREE RECEIVER
AND I AM REALLY NOT DISPUTING THAT
BUT AS FOR AS MYSELF I NEVER EVER HAVE HAD ANY PROBLEMS
AND HAS OF THE THE OVER ONE HUNDRED THOUSAND PLUS THAT WAS SOLD
I HAVE ABSOLUTELY NEVER EVER HEARD ANYTHING ABOUT ANYONE SENDING ANY
LOWER RECEIVER BACK
AND WE WERE CLOSE FRIENDS
BUT I KNOW TIMES HAVE CHANGED WITH BETTER TECHNOLOGY
BUT AS FOR MYSELF I WOULD PUT MY LIFE ON THESE LOWER RECEIVER
BECAUSE I HAVE BEEN USING THESE LOWER RECEIVER SINCE THE EARLY 1981 OR 1982
SO AFTER ALL THESE YEARS
THEY ARE STILL GOING STRONG
BUT I WOULD STILL APPRECIATE IT
IF YOU ARE ANYONE WHO IS READING THIS
TO GIVE ME THERE OPTION OF WHAT I HAVE AND WHAT THEY THINK
NOW THAT MY CLOSE FRIEND IS NO LONGER IN THE GUN BUSINESS
I WILL BE LOOKING FOR THE NEWEST VERSION OF THE LOWER RECEIVER
AND I HAVE ALWAYS APPRECIATED THE OPTION OF THE PEOPLE
WHO ARE WRITING THESE ARTICLES
I AM AND OLD DISABLED VETERAN
AND I REALLY LOVE TO SEE ALL THE NEW GUN PRODUCTS THAT ARE COMING ON THE MARKET
THANK YOU FOR SUCH A GREAT ARTICLE ON LOWER RECEIVER AND ALL THE OTHER ARTICLE
THAT I READ ON A REGULAR BASIS
AND HAVE A VERY BLESSED DAY
THANK YOU
DENVER
Breath...
I won't read anything written in all caps with little to no punctuation. Why do people do this?
They may be gun savvy, but not computer, or English class savvy.
Probably because they don’t know any different. The man wrote that he is elderly, disabled and a veteran. So, in my book, those three facts increase my respect and compassion for him.
If he wants to write in all caps, God bless him. Caps all day it is!
We can all learn to have a little more compassion. Someday we’re gonna be right where he is. Lord willing and the crick don’t rise. CHEERS!
Agreed
I found it interesting enough, he says cast was good enough for him and Dallas Texas SWAT. Just imagine some humble guy at a hardware store parts counter is writing it on the checkout computer with his pointer finger.
Any reviews on the polymer lowers that are coming out now?
I've heard amazing things about GWAC, the only poly lower I have is a Tennessee Arms lower. I'm not a huge fan, mine had a lot of fitment and finishing issues.
Beware of American Muskets Billet Lowers - I have one, it is basically an expensive AR lower shaped paperweight - they have ZERO customer service skills and use childish memes when you contact them about their defective product.
The hole for the front pin is slightly too low, so an upper cannot be properly mounted.
It is off just enough that you can see through the gap between the upper and lower at the rear when you hold it up to the light.
Tried 6 different manufacturer's uppers on it with the same results.
It is true, as you've noted in the article above, that cast aluminum is not as strong as forged aluminum, but did you know that in the 1950s and 1970's they developed zinc aluminum alloys? These are much better for making lowers, and are designed for the sand casting methods that most DIY Homebrew hobbyist foundries use.
When comparing zinc aluminum alloys with forged aluminum, forging has no particular advantages, and with home DIY anodizing and etching, it's possible to come up with a lower that's every bit as good as a Factory forged aluminum lower. As far as the finish that you come out with, this depends upon what anodizing process you use, and the level of polishing that you want to apply.
I like the look of a dull, black-matte finish, but that's my personal preference; to achieve this effect, you would use drain cleaner (lye) to leach into the zinc aluminum, and black RIT dye in the anodizing process, using a battery charger as power supply, witness the plethora of YouTube DIY videos on this subject :-)
FYFI https://en.wikipedia.org/wiki/Zinc_aluminium
I did not see any AR 10 lowers. I have shot AR 15 in competition for some time and decided to move to 308. I am currently owning an M1a that is accurate and a Precision semi 308 which is a great rifle. I would like to build a very good 308, My other rifles are very good I just want to build a 309.
This is our picks for best AR-15 lowers. We have a separate article for AR-10 lowers.
I have 3 Anderson lowers on all 3 of my builds. All 3 very tight matchups with my uppers no slop, no play. I paid $33 ea not including shipping and FFL transfer fee's. None were "scratch & dent" specials either. I did very extensive research before I did my builds and I agree that Anderson should get top pick for "Best bang for your buck" I'll probably never need a, "High Speed Low Drag, super Tacticool" AR-15 so Anderson it is! My AR builds individually cost less than the 2A Arms Lower. I'm sure the 2A Arms is of the highest "quality" one can buy. But I'd rather have an AR for each family member when we go shoot than a $1000 AR that I don't want scratched or touched. I'm helping 2 buddies build AR's they both opted for the Anderson lowers. In your review of the Aero Precision lower you state they are just like the Anderson lowers but their logo is better looking. WHAT?! Really? $33 for an Anderson or $90 for an Aero? I'll save the $57 and buy 7 or 8 CPD aluminum mags.
I have 3 anderson lowers. All of them were sloppy. One on a stag arms upper , one on a psa upper , and one on a rugged upper.
Upper and lower fit is a crapshoot when you buy them separately from different makers. Why, when they were both touted as milspec? The blueprints themselves tells the story - + or - up to .015". That's a spread of .030", and what the gun assemblers do is to stack the dimensions in their favor, sorting them in batches to get a precision fit.
We get what we get and make them work.
I have trained with highly used/abused GM M16's, where I could stick a playing card thru the upper/lower, and have unboxed brand new FN's that were as close and precise as anyone could ask. After three years of qualifications and field use, the FN was loosening up with a perceptible click. Just like the old GM.
And, I have built them, too. My first was an absolute pin pounder - I literally had two different makers and whichever way I assembled it, the last pin would need to be literally tapped in with a dead blow. Until about the 5th or 6th time, at which point all it would take is thumb pressure.
The second AR was a bit loose from the beginning.
The accuracy? I can fire Expert with either, and did in the day. A loose fitting lower or not, you don't suffer accuracy. Since the sights are attached to the upper, it makes no difference at all, whatsoever. It's not like a manual bolt action - the AR is different. Using old school concepts to assess how it might shoot because of fit and finish does not translate from old technology to new. To be precise, the fundamentals don't change, but the engineering did, and understanding that engineering is where a lot of shooters miss the bus. Being proficient with using the weapon does not in and of itself create an understanding of what is going on. A manual action firearm is not a good example of what happens in a dynamically self loading one.
Keep in mind the AR15 is the absolute closest we have ever come to buying parts from all over the country and then taking 45 mins to assemble a working firearm with no filing, fitting, or finishing needed. You cannot do that with a firearm which requires you to press fit the barrel into the receiver, or file trigger parts to get the correct action. Hence, why there is no huge assemble your own AK rifle. At all. None of that is necessary 95% of the time assembling an AR, because of those =/- .015 specs. Any other design, you'd be filing them to fit worse than a pre 63 Winchester, which is exactly why they quit making such horrible parts that required all the hand fitting. It was driving them out of business. Make good parts up front that don't require gunsmith level handicraft, and then you get what Stoner designed, a MODERN manufactured weapon that can literally be built from a pile of parts.
Hundreds of thousands do it all the time. Just don't expect bespoke craftsmanship when you aren't capable of doing it. You have to buy that - dozens of uppers, lowers etc and then match them all up to get there. Or, be a well trained machinist or smith who has years of experience. The rest of us just assemble them and shoot them, getting good results, whether or not the upper and lower really fit all that well. However it turned out, it will loosen up, and for the most part, it won't make any difference.
Look at the history of the 1911 and you can easily see that trying to make it a tightly fitted precision target pistol is exactly how you screw it up. It wasnt designed or intended for any such thing, and the same goes double for the AR15. Again, the fundamentals are the same but the engineering is highly different.
I want to buy an Anderson Lower first and then an Upper. But not at the same time because of budget. Can I buy a Lower now and then get an Upper 2 months later and will they fit. It's all because of my budget. Cannot afford to get them at the same time. . Hope you can help me.
They will almost 100% "fit" if mil-spec but might have some slop. It won't affect accuracy or anything but you might have some movement/sound that bothers some people. Even if you buy together unless it says matched pair you might still have the same problem.
I just built my first AR. I picked up a Anderson lower. A month later fuck the rest of the upper and lower build kit from PSA. All the parts I got for it fit like a champ.
I believe so, just makes sure of what you have and buy accordingly to the extra parts.. Meaning Mil spec, or not. Those parts do not match. It's either one or the other
F1 skeletonized receivers are heavier than standard milspec.
Does any AR Lower fit any other brand upper and viece versa? Are do they have to be by brand only? I need an answer, please..
It almost always will if they are mil-spec. Fit/slop might differ though.
You might want to buy your upper and lower together. Even from the same maker you can have fit and finish problems. I have Anderson Lowers and Anderson slick side uppers. They fit and work, but there is an EXTERNAL spot where the two don't exactly jibe with each other. The problem also exists with the Spikes lowers I have. It's something funky with the uppers. It's purely cosmetic, but if you have ODC it'll drive you nuts. Finishes also vary, but you can match up your upper lower and handguards with Cerakote or Durakote and give everything a uniform finish and custom look.
None of my issue rifles had exact match of receiver profiles from upper to lower. I don't believe it was even required. After the Army decided to refit original M16's and upgrade them to A1 - hand stamping the nomenclature on the lower - some of the misfit was even more pronounced, altho they pinned together well enough.
It a combat based weapon, having the lumps and bumps match perfectly won't do anything to make it more precise or help the bullet knock them down deader.
I know you can't touch every company but was curious if you looked at Mega Arms and if there was any reason they weren't mentioned. great article. Thanks,
Hey Rich, I've heard of them but simply have never used one.
I have built 2 builds on the Mega, Great sets! They have sold out now and my goto is Zev Tech. or Aero.
Thanks for the write up...do you know who machined the "model skeleton "lower in the photo ?
I really really love New Frontier Armory's C-4 Billet set. You can purchase the set for a mere $230 ish. The lower features an integrated trigger guard, upper-to-Lower tension screw, threaded bolt-catch screw, and a threaded plug for take-down hole. The lower weighs in at 10.4 oz & the upper at 12. oz, not ideal for a lightweight build but definitely great quality for an affordable billet set up which I believe this set to be just as good as the $500 sets. They also make a polymer ar 15 receiver set which is supposed to be very durable. They also make 9mm, 80% & forged receivers. Want an upper receiver with a side charging? They make em in 9mm & 556. I'm currently building an ar 15 battle rifle using New Frontier Armory's C-4 Billet receiver set and I'm very pleased with the quality & look.
Hi Eric,
I've rapidly become a fan of your articles and advise - thank you! I'm a huge fan of the AK platform's ability to shrug off any and all environmental factors and still go bang every time. I'm considering building my first AR platform rifle and I have a question for you: What feature(s) or component(s) should I put the most money/focus into in an attempt match this level of reliability?
Thank you!
Hey Tony...we're working on a series of the best parts/features for a custom AR-15 build with a couple tiers of different budgets...so stay tuned!
I have done several builds off the Aero Precision upper/lowers. Really like there M4/M5 Enhanced upper, strong & makes a simple build. If you want to get a little wild go with the C.O.P upper. Did one build with this. Look out for there specials or shop dealers & you can beat the web site retail.
Anderson all the way, 356 Builds by Customers in Standard and RF-85. Can't go wrong and why pay more..K.I.S.S. fro a FFL and Operator
My first build was a 16" .223 that started with an Anderson complete lower. Love it! Now I'm building a 8.5" .300BO pistol starting with an Anderson stripped lower.
Well written article. Thanks for taking the time to put this together. I run a YouTube channel called Green Light Shooting and am doing my first AR build on there. I'll be sure to send the viewers to this link for more info on lowers.
Chad
youtube.com/greenlightshooting
I'm currently in the middle of a build using a new companies receiver set. So new in fact the serial number is 0000023 It's a local manufacturing company called rss defense the receiver weighs in at just over 7 ounces. That's both upper and lower and was priced at 250. I'm very impressed with the rifles they make so I decided to make one using their Receiver.
I currently own a built AR with Anderson lower. I recently bought a Seekins billet trigger guard to replace the flat one that came with it, and it will not fit...a hair too long. Is this common with the Anderson lower?
Not all billet items fit mil-spec recievers. You have to read and see if its compatible with what you are building. Seekins precision usually only fits billet recievers.
Used anderson lowers in 5 builds now great quality never had a prob. And I agree aero uppers best bang for your buck hands down
Awesome!
Wow this was a pretty awesome and in depth article. One of the best I've read. Thank you!
You're welcome Justin...glad I could help!
hi Eric. this will be my first ar so looking into a budget build. I may take your recommendation of going with the Anderson mfg complete lower. just wondering what you would recommend for a complete upper assembly that will mate it the best. don't want to spend over $400 for the upper. also, have you any input on Palmetto brand? thanks in advance!
Hey Peter, I really like my Aero Precision upper...you can check out my recs for uppers here: https://www.pewpewtactical.com/best-ar-15-upper-receiver-assemblies-money/
Palmetto is good for really budget builds but I'd recommend saving up a little more.
Now that Ruger is selling stripped lowers and you can get sig saur stripped lowers those would be my primary choices.
Thanks for your input!