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Finding the best AR-15 lower receiver for your next build may be a daunting task yet there is no room for mistakes given that the lower receiver is considered the actual firearm.
You have searched the web for the best but you still haven’t made up your mind. How about taking an informative tour with us? Why not replace the uncertainty with facts?
You need not worry about getting confused by so much information anymore. This article will review the best AR-15 lowers to make it a smooth sail for you as you make your pick. Keep reading to learn more.
Types of Lower Receivers
Lower receivers are classified by the material and construction process into the following four types:
Cast Aluminum Lower Receivers
These are the weakest since the aluminum is only melted and poured into precast molds, let to cool, and extracted for the final machining to fine-tune them. However, they are still strong enough for use and you won't have to worry about them malfunctioning.
Polymer Lower Receivers
Polymer is a weak material but it makes super light, easy-to-drill lower receivers. Some makers may reinforce them with metal inserts to boost their strength. They are highly resistant to abrasion, impact, and chemicals.
Billet Aluminum Lower Receivers
These are stronger than the cast ones and are made from solid aluminum without melting it at any point. This makes them remain stronger and more ready for manufacturer customizations like built-in trigger guards.
Forged Aluminum Lower Receivers
Forged lower receivers are the strongest among these four types since the compression process in their making leads to highly compacted receivers. Being the strongest option, they come at a higher price point but with great value for it.
Aluminum receivers come in two alloy options - the 7075 T6 and 6061 T6. The 7075 T6 is the stronger of the two. 6061 T6 is more resistant to corrosion, although you won't have to worry about corrosion once you find a receiver with a good finish and coating.
To clear the air, you may come across the heavier, stronger, and pricier titanium and stainless steel lower receivers. However, these are very rare to find.
Why Did These AR Lowers Make Our List?
A combination of several features makes a lower receiver a great option to warrant its inclusion in our carefully considered list. These are discussed below.
Machining and Finish
Although most AR lower receivers are made of 7075 T6 aluminum, it is important to check how the machining has been done. With no flaws such as machine lines, badly cut holes, cracks, or bubbles in the coating, these lower receivers secure their place in our list. The absence of such flaws means your receiver is safe from exposure to chemicals, atmospheric elements, and corrosion.
Threading
Threading ensures parts fit together properly with no room for dangerous outcomes resulting from slips, slides, or total falling off of parts of the gun. The receivers we have reviewed cross the threading threshold and assure you of safety during assembly and use of your rifle.
Construction Material and Type
Durability should be one of the foremost things to consider when buying a lower receiver.
A material of high quality like the 7075 T6 aluminum makes for a strong receiver.
Polymer, billet, and forged receivers maintain a good balance in form and function, while still fitting your budget just like the lower parts kit components fit well into them.
F-1 Firearms UDR-15 3G Style 2 Stripped Universal Billet Lower Receiver
Quick Take | Best AR-15 Lowers
Here are the best AR-15 lowers:
Review of the Best AR-15 Lowers
Let's take a look at this year's top picks.
Best Overall:
Anderson Manufacturing - AR-15 Stripped Lower
Pros
Cons
What Recent Buyers Report
Recent buyers find fault with the Anderson AR-15 stripped lower for its lack of an inbuilt trigger guard. It proves hard for some buyers to find the right guard to go into this space.
Why it Stands Out to Us
This lower stands out since it offers buyers a wider range for customizations because the right side is left largely empty. Every buyer has the chance to create a highly customized lower for a more personal touch and appeal. It is also a unique idea leaving room for including the auto feature marking as part of the customization process for users to comply with laws on automatic rifles in applicable states.
Bottom Line
For an even greater allowance to customize your rifle, this lower makes a good fit for gun lovers who prefer to custom-build their rifles to reflect their personal preference while still managing to remain within the limits of their budget.
Best AR-15 Ambidextrous Lower Receiver:
PSA AR-15 SC Flag Lower
Pros
Cons
What Recent Buyers Report
Recent buyers uphold this stripped lower receiver as a good fit for users who can easily use both hands to handle and shoot from a rifle. The flag adds to the beauty of the lower and makes other gun lovers envy and compliment its users.
Why it Stands Out to Us
The two unique features that make this lower stand out are the flag and ambidextrous capacity. The flag is a unique addition to the aesthetics. The ambidextrous feature makes it possible for buyers who can comfortably use both hands with equal precision to explore their ambidexterity. This becomes a key feature that such buyers identify with and praise the gun for.
Bottom Line
If you can easily use both hands and still achieve a remarkable degree of accuracy and efficiency, then this is the lower receiver for you. It runs out of stock fast since it is popular. As such, it is important to keep a keen eye on the market for its availability to make your order so you won't have to wait a long time for new ones to be made.
Pros
Cons
What Recent Buyers Report
Recent buyers consider this Palmetto State Armory lower receiver a great investment given its high quality, fast shipping, and considerate customer care service, especially for California buyers. They recommend it as easy-to-assemble, with parts fitting in well.
Why it Stands Out to Us
This lower receiver stands out to us given its triple choice fire selector range between safe, semi-auto, and ability to use full-auto after installing automatic components. It is made of 7075 T6 aluminum that is forged for strength and durability and the ability to withstand rapid fire.
Bottom Line
This is a high-quality lower for the rifle that will assure you of durability, lightweight, and compatibility with parts and calibers from various manufacturers. If you would love to turn it into a full-auto or burst mode rifle, there is an allowance for that when you buy the right conversion components.
Pros
Cons
What Recent Buyers Report
Recent buyers like the PSA Stealth as it comes in completely assembled, saving them the lengthy process of finding fitting parts. The butt holds firmly against the body. The smooth trigger is gentle on the trigger finger even without being high-tech.
Why it Stands Out to Us
With super fast shipping and full assembly, this stealth lower receiver is a unique device. It has an unnotched hammer for the best hammer strike. You can easily take the trigger down and polish it on your own for an even smoother feel so it's more gentle on your trigger finger while still eliminating chances for dangerous slips or slides.
Bottom Line
Buying a fully assembled lower receiver that saves you time couldn't get any easier. The parts are easy to fit in, making using your rifle right away a possibility. Time is saved that would have been spent looking for matching lower parts kit constituents.
Lightest AR-15 Lower Receiver:
F-1 Firearms UDR-15 3G Style 2 Stripped Universal Billet Lower Receiver
Pros
Cons
What Recent Buyers Report
Recent buyers praise this lightweight lower as a safe device because of the oversized trigger guard. The billet make gives the lower a new design with improved aesthetics that appeal to most buyers. Some users report high risks of recoils, which cause reduced shot accuracy and increased stress to the body of the user.
Why it Stands Out to Us
The billet construction mode makes this lower stand out from others on our list. The mode allows for the new skeletonizing design that makes it possible for the manufacturer to make manipulations on weight and aesthetics for a light lower with a fine finish. Milling out unnecessary surfaces is a plus feature that rids the lower of junk.
Bottom Line
Finding a junk-free lower with unwanted surfaces removed is a rare feat. This universal lower from F-1 Firearms makes that a reality for you so that you get high quality and great value for your money.
Best AR Lower Receiver for the Money:
PSA AR-15 Complete MFT Battlelink Classic Lower
Pros
Cons
What Recent Buyers Report
Recent buyers love this receiver as it comes in complete and ready for use. The price point is a major feature that most recent buyers commend for the value the receiver offers. Just like its other PSA counterparts, it is easy to order, ships in fast, and the customer care service is more than ready to listen to your complaints or compliments.
Why it Stands Out to Us
This is a unique lower because of the wide range of calibers it works with from .204 Ruger to .450 Bushmaster, with at least 10 more options in between. Assembling the receiver with lower parts kit from the same manufacturer ensures it stays safe as the parts fit in well with no need for any manipulations. The 6-position adjustment is also a unique feature that sets this pistol lower apart from most of the lowers on the market.
Bottom Line
For a pistol lower, this is a great fit for pistol enthusiasts who would love to have their lower fully assembled to save on time looking for parts and assembling. You will have a better usability experience because of the 6-position, which allows you to customize your rifle to find the best shooting position for you.
80 Lower Legal Issues
Lower receivers are highly regulated across most states. The following are some of the safety aspects you should keep in mind.
Legal Buying Age
The very first thing to consider on safety before buying any lower receiver is the prevailing local, state, and federal laws and regulations on the possession and use of firearms. Since lower receivers are considered firearms, you have to ensure that you have attained legal gun handling age and obtained certification to use a rifle. Failure to do so will land you in prison once they discover you broke any of the laws. The legal age for gun buying and handling is 21 for most states.
Personal Health Concerns
The state of California recognizes that handling guns or their parts can cause lead poisoning, which may cause cancer and reproductive harm. It is thus recommended that you should wash your hands thoroughly with soap and running water immediately after handling.
Automatic Rifle Restrictions
Although some of the flowers we have reviewed in this article come with the option to customize them to full-auto, this is not easily achievable. Other than the lengthy approval process, you may only be allowed to do automations after becoming a licensed firearms assembly expert. If you later choose to abandon this licensing, you have to turn in, sell, or destroy the automated guns you have built in the past to reduce the chances of them falling into the wrong hands.
Comparison Overview
It's worth looking at the similarities and differences between the types of lower receivers as they appear below to help you make a more informed decision.
Billet vs Forged Lower
Similarities
Both receivers are made of strong aluminum of either 6061 T6 or 7075 T6 alloys.
Differences
Billet lowers are made from a single block of aluminum by using machines to carve them out in a time-intensive process that results in a lot of waste material. This intensive process makes them come at a higher price point at times, compared to the even stronger forged lowers.
Forged lowers are made by hammering hot aluminum leading to massive compression that makes the lowers extra strong as the metal grains are more compacted against each other. This makes forged lowers the strongest compared to their cast and billet counterparts.
Polymer vs Aluminum Lower
Similarities
Both lowers have lightweight characteristics since polymer and aluminum are both light materials that retain this lightness even when more material is used to make the receivers.
Differences
Polymer receivers are less strong compared to aluminum lowers since the resin used to make polymer lowers is weak. As such, metal inserts may be added to some parts to make the polymer stronger and more rigid.
Given the easier construction process and low cost of materials, polymer lowers sell at lower prices than the forged ones.
How to Assemble an AR-15 Lower
To assemble an AR-15 lower, follow the steps outlined below.
To make it easy and error-free, the trick lies in having every part on hand, with the right components that go with it. Have all the springs and detents close to hold in place every part you fit in. This helps you avoid having the parts fall off during assembly, or remaining loose.
You will need a hammer and flathead screwdriver to drive in nuts or bolts by hammering or screwing. Ensure all the holes for each set of fitting parts are lined up before driving in the screw or nut.
Start by fitting in the magazine catch with the help of one of the chosen dummy rounds to bring the catch to a flash position. You will then install the trigger. Place the trigger disconnector on top of the trigger spring before placing the trigger group in place. Hold it steady by fitting in the trigger pin.
Install the hammer and fasten it with its pin. Next, install the selector switch and fasten it with its detent and spring. The grip comes next and you will hold it in place using its flathead screw.
Fasten the lower on a bench block to hold it still for the next installations. Put the takedown pin into its hole. Thread on the receiver extension and fasten it by hammering in the castle nut. Insert the bolt catch and hold it in by using a hammer to knock in the bolt catch pin.
Install the trigger guard with its detent and pin. Hammer in the pin to fasten the guard.
Complete the receiver extension by installing the buffer spring and buffer. Finally, install the butt on the back of the receiver extension and lock it in place.
The video below gives you a full overview of the assembly process we have just described. Be sure to refer to it to ease following every step.
Conclusion
We have so far learned the various types of lower receivers, legal issues concerning them, and how to assemble an AR-15 lower. The items we have reviewed make for great choices and you only have to narrow down to one according to your preference, available budget, and how you will use the gun.
People Also Ask
Still have some questions? Here's a close look at some of the questions people ask about lower receivers.
Do You Need an FFL to Buy a Stripped Lower Receiver?
You will need an FFL (Federal Firearms License) to buy a stripped lower receiver since it is the most legally controlled and regulated component of a rifle. The FFL is issued by the Bureau of Alcohol, Tobacco, Firearms, and Explosives (ATF) to individuals to allow them to use firearms. The selling company, which is also issued with an FFL will require you to show proof of your FFL before they deliver your lower receiver.
Is an AR Lower a Firearm?
An AR lower is considered a firearm. Lower receivers are recognized as the main component of a gun, and the most critical one for its functioning. As such states consider them a firearm and issue regulations and laws to control their sales and usage.
Does an AR Lower Affect Accuracy?
An AR lower has fewer moving parts and is thus less likely to cause reliability problems, unlike the upper receiver. This means that the lower does not affect accuracy at all. After all, the sights come in the upper receiver.
What Calibers Fit in an AR-15 Lower?
The following calibers fit in an AR-15 lower:
- .204 Ruger
- .22 Nosler
- 6.5 Grendel
- .224 Valkyrie
- .300 Blackout
- 6.8 SPC
- .25-45 sharps
- .223 Remington
- .450 Bushmaster Among others.
Note that not all the listed calibers fit into each lower since some may have different specifications based on the manufacturer.
What is a 80 Lower Receiver AR-15?
An 80% lower receiver AR-15 is one that has not yet been manufactured to the firearm level. To make it reach the firearm stage, the lower parts kit components have to be fit in after making the necessary cuts and drills to accommodate the parts. Most 80% lowers come as raw aluminum, which you can finish from the silver color to black or gray once you are done fixing the parts.