Best AR-10 Lower Receivers (2021) – Reviewed

Best AR10 Lowers

The AR rifle is a well-loved shooting platform by many firearm enthusiasts simply because of the level of customizability it offers. Under the U.S. Law, the lower receiver of an AR-10 rifle is actually considered to be a firearm itself as it houses the fire control group. 

The AR-10 is designed to be a precision shooting rifle, meaning that it is capable of firing the heavy .308 caliber. With that in mind, the accuracy and precision of the AR-10 rifle are of prime importance, which will inevitably be widely influenced by the AR-10 lower receiver. 

In today’s article, we will be going through some of the best qualities of a good AR-10 lower receiver, its ideal manufacturing process, as well as the compatibility between AR-10 and AR-15 lowers. We will also be going through some of our top picks for the best AR-10 lower receivers available on the market now in hopes of helping you make a better-informed buying decision. 

Lowers Name Editor’s Comment Rating Get The Deal
Black Rain Ordnance Stripped Upper & Lower Receiver

Most Recommended Option

1. Machined from 7075 T6 bullet aluminum
2. Threaded bolt catch pin hole
3. Features an integrated trigger guard

10/10 SHOP NOW
Aero Precision – 308 AR M5 Lower Receiver 1. Features an integrated trigger guard
2. Hard-coat anodized finish
3. Has a flared mag well that accepts PMAG
9.5/10 SHOP NOW
Mega Arms Maten Billet Receiver Set (Upper and Lower) 1. Billet machined receiver set
2. Features oversized integrated trigger guard 3. Fired magazine well opening
8.5/10 Currently unavailable
James Madison 80% Lower Receiver with Jig 1. Made from hybrid polymer and fiber materials
2. Webbed mag well
3. DPMS-compliant lower receiver
7.0/10 Currently unavailable
​​Cross Machine Tool Billet Receivers (Upper and Lower) 1. Made from 7075 T6 aluminum
2. Hard coat anodized finish
3. Two-in-one assembly set
7.0/10 Currently unavailable

How to Pick a Great AR-10 Lower Receiver? 

AR-10 lower receivers can either be just a simple CNC-machined chunk of metal or a full-fledged functioning firearm that can fire off ammunition. A complete AR-10 lower houses a few critical components including the trigger group, pistol grip, safety selector, magwell, and the buffer tube catch. 

However, there are a few important points to consider when looking for a good AR-10 lower. A few such criteria to look into are its compatibility with different uppers and the availability of suitable magazines. We will be going into detail for each point below.

Platform

The first and most basic factor to take into consideration is what type of platform is your AR-10 lower. Compared to AR-15 rifles, AR-10s are not as widely used by many and there are only a few standardization options for it. The two major platforms of AR-10 are namely the DPMS – LR 308 and the Armalite AR-10. If you’re upgrading your lower, do make sure to check again and choose the right platform so that you won’t have to change other components subsequently just for them to fit. 

Customization

Another aspect to consider is the preferred level of customization. While some prefer to purchase ready-made lowers so they can quickly set it up and head to the shooting range, others like to machine them as buying a complete lower will require an FFL but an 80% lower doesn’t. Nonetheless, getting a finished lower receiver will ensure precision, helps you save time, and most purchases even cover you with a warranty. 

Trigger Guard

Other than the two factors listed above, another crucial part to look into is the AR-10 lower’s trigger guard. A good AR-10 lower receiver must have an integrated trigger guard to ensure a stronger lower. However, some may prefer to swap it out with a trigger guard of their choice.

Forged vs Billet Lowers – Which is the Best?

This question is a little more complicated to answer. But first, we need to understand that AR-10 lower, and any other lower receivers for the matter, are actually manufactured by three production methods, which include casting, billet shaping, and forging.

The casting process will involve pouring molten metal into a cast or die to give it shape. The metal produced from casting can be quite brittle and has a lower quality compared to the rest. 

Billet shaping uses CNC machines to help shape a solid chunk of metal into the desired shape. The metal here is already prepared, so all that’s left to do is cutting and lathing it. 

Finally, the last method is metal forging. Forging is a procedure that’s been used for crafting metal for centuries. Forged receivers are considerably much better than billet ones. The reason for that is because forging uses hot metal that has been regularly heated and beaten up, which results in its grain to mix, making it firmer and less brittle. 

While receivers manufactured from the billet method have very clean and pleasing aesthetics or designs, forged AR-10 lowers are technically a bit harder and more durable when compared to billet lower receivers. So, if given the choice, it is advisable to opt for a forged lower receiver. 

However, the main takeaway is that actually none of this really matters, it is all mainly just a matter of mental satisfaction as billet receivers have never been actually reported or observed to underperform compared to forged ones, although there’s still a slight margin. 

So, if you’re into hunting and bringing your rifle outdoors, subjecting it to tough use and heavy abuse, it is better to go for a forged receiver. If you’re more inclined towards competitions and precision shooting, billet receivers will do just well for you. Furthermore, billet receivers are also much more aesthetically pleasing. 

The Difference between AR-10 vs AR-15 Lower Receivers

Those who are hoping to use or swap their lower receiver components between AR-10 and AR-15 rifles are, unfortunately, going to be disappointed. Despite the inconvenience, there is one simple reason behind this, which is that the calibers of the AR-10 and AR-15 do not match. The AR-15 fires off the .223 REM whereas the AR-10 shoots the .308 caliber rounds which are heavier and larger. Hence, there are certain dedicated parts in the AR-10 lower receiver that have been designed to accommodate and fire such bullets. 

While most of the lower receiver parts are not interchangeable between the AR-10 and AR-15, there are some that are. 

The parts that are not interchangeable are the magazine, the magazine catch, the takedown pins, the bolt catch, and pistol grip which are all unique to each platform. The AR-10 magazine houses .308 cartridges while the AR-15 magazine holds .223 rounds. The magazine, as well as the magazine well of the lower receivers, are hence bigger than the AR-15. 

As mentioned earlier, the AR-10 rifle was primarily designed for heavy usage and combat, which is why it requires larger parts. Also, due to its more powerful firepower and caliber, the AR-10 is somewhat bigger than the AR-15 too, which means the takedown pins and bolt catch are also bigger, hence impossible to swap between them. 

The only part in the lower receivers that is interchangeable is the trigger springs and trigger, which you can swap between the AR-10 and AR-15 rifles without a problem. 

Reviews of the Best AR-10 Lower Receivers

Now we’ve finally come to the most interesting part of our article – the best AR-10 lowers currently available on the market. As you go through the list, make sure you take note of any characteristics and features that stand out to you. This way, you’ll be able to find out which matches your ideal description of an AR-10 lower. Pick one that’s the closest match and you’ll know for sure that it’s a winner. 

So, let’s dive straight into what produces have made it onto our list and why:

1. Aero Precision – 308 AR M5 Lower Receiver

Best AR-10 Lower- The Best Overall

​SHOP NOW

The Aero Precision AR-10 lower receiver is equipped with a solid black finish and is designed to accommodate the Gen 1 DPMS .308  components, particularly the DPMS magazine and upper receiver. The lower chambers in the .308 Winchester cartridge – a common caliber among most Armalite AR-10 lower. Just to let you know, this cartridge is actually slightly larger and longer than the standard AR-15 223 Remington cartridges, which is why you might notice a flared and bigger mag well that’s designed to accommodate larger rounds with ease. 

As for the assembly, the AR-10 lower receiver is forged with a stripped style, which is said to be one of the best because it produces a strong and lightweight product. All in all, this lower lets you build a custom-made large-bore AR rifle from the ground up. 

In terms of quality, the Aero Precision .308 AR lower receiver is measured with mil-spec dimensions with an anodized hard coat finish to ensure accurate component interface and excellent quality, therefore ensuring better durability in the long run. The coating also works to prevent corrosion from occurring as you bring your firearm out under rainy weather. 

The mil-spec dimensions of the m5 lower receiver mainly refer to the buffer tube or also-known-as as the receiver extension. A mil-spec buffer tube is two-hundredths of an inch smaller than commercial ones and they do have more versatile options for aftermarket stock upgrades in the future. 

On top of that, the Aero Precision 308 AR rifle is machined from 7075 T6 aluminum and coated with a matte black hard-coat anodized Mil 8625 Type 3 Classic 2 finish to further contribute to its excellent corrosion resistance. Furthermore, the Aero Precision 308 AR lower receiver even comes with a solid integrated trigger guard that is firmer compared to any plastic piece in the market. The safety selectors markings come with 45, 60, and 90 degrees, which work with standard safeties as well. 

The Aero Precision 308 AR M5 lower receiver features a mag well that is clean with a non-rough polished surface that features a higher front part to make it easier to get the magazines inside and seated without needing to lift it up and down. Another plus point for this DPMS style lower mag well is that it also accepts PMAG style magazines. Plus the magazine is flared out quite generously to ensure speedy reloads. 

Last but not least, the lower receiver has a rear takedown pin detent hole that is threaded 4-40 to ensure that the set screw retains the takedown pin. With this feature, you won’t need a roll pin, all you need to do is just unscrew it, put it in place, and screw it back to complete the installation.

You would like this if:

  • You want an integrated trigger guard and selector markings
  • You want a receiver with a hard coat anodized finish
  • You want a polished and flared mag well that accepts PMAG
  • You want a stripped/  forged assembly
  • You do not want to use roll pins

​SHOP NOW

2. Mega Arms Maten Billet Receiver Set (Upper and Lower)

Runner-up

Fortunately, Mega Arms Maten comes with both upper and lower receivers together for you to kill two birds with one stone, instead of having to waste time and money looking for a separate upper receiver that fits. One thing to note is that this lower receiver is only compatible with the Mega Maten upper receiver. With that being said, this receiver set from Mega Arms Maten is an outstanding platform for shooters to build a versatile and robust AR 308 rifle thanks to its ability to accommodate the widest variety of aftermarket components. 

The purchase includes both the billet machined upper and lower receiver, a Meda Arms billet charging handle, a dust cover door, bolt release, bolt catch pin, and pivot/takedown pins. The bolt even has a complete ambidextrous feature that’s super user-friendly and can be used to release the bolt from both sides. 

As mentioned in our discussion earlier, the billet style receiver combo is actually a lot more complicated to make compared to the forged style. The billet assembly consists of a CNC machined metal that is machined and carved from a single billet block stock to form the lower receiver shape. This assembly style then allows you to make easy modifications. The billet upper and lower receiver even has laser engraved T-numbers on top of the Picatinny rail for a rather impressive and rugged design. 

The receiver even comes with an extra metal beefing up the attachment point for the buffer tube to eliminate any potential failure point in the future. On the rear, you won’t see any holes for detent and spring at the extension because of the altered set screws position. The safety selector on the other hand comes with fire and safe pictograms for a clear visual aid on whether your battle rifle safety is on or off. 

Other than that, the magazine well opening is also generously flared while the internal chamber aids in quick and easy magazine insertion/reload. The integrated trigger guard is oversized and is even integrated for enhanced rigidity and strength on top of providing plenty of room for a gloved finger. 

A little more on the integrated trigger is that it comes with a set screw instead of a roll pin for added convenience. This means that you won’t need extra tools to install it. All you need to do is screw the set screw pin in to attach the 308 upper and lower receiver securely in place. 

You would like this if:

  • You want a billet machined receiver set of upper and lower receivers.
  • You want an oversized integrated trigger guard. 
  • You prefer flared magazine well openings.
  • You want to use a set screw pin instead of roll pins. 

3. James Madison 80% Lower Receiver with Jig

All James Madison Tactical (JMT) lowers are equipped with a machining jig that has a 3-piece solid construction made from rigid plastic. Other than that, the JMT even has great machining instructions for you to forget about the need of adding modifications and completing the receiver. Overall, it can be said that JMT has incorporated its own unique formula that consists of hybrid fibers and polymers with additional reinforcements in high-stress areas to create one of the best products in the market. 

Considering the fact that the James Madison lower receiver is only 80% assembled, the purchase and delivery of this 308 AR lower do not require an FFL license. That being said, the installation for this 80% lower will require a little more effort and will involve installing the trigger, hammer pin, fire control group, trigger slot, and safety selectors. The lower receiver even has an extended upper left mag well box section and an upper fire control box section. 

In terms of construction, this AR-10 lower receiver is made from polymer80 material and is engineered to mil-spec tolerances. Since it is machined from a durable fiber polymer material, owners won’t have to worry about the receiver corroding in the long run as they would in an aluminum lower. 

Furthermore, the Armalite lower receiver is DPMS compliant and features new JMT Gen 2 logo markings. The unique features even extend to its extended bolt release pin posts while the webbed magazine wells on both the left and right side of the receiver are able to accommodate Magpul magazines. Apart from an impressive mag webbing for better hand grip support, the flare on the mag well is actually curved out rather than a sharp line for better ergonomics. 

The AR-10 lower receiver is even equipped with a threaded brass insert to let you tighten the grip screw down without having to strip the threads. Certain key areas of the .308 AR lower receiver are also reinforced for enhanced durability. 

You would like this if:

  • You want an AR .308 lower receiver made from hybrid polymer and fiber materials.
  • You want webbed mag wells.
  • You want a DPMS compliant lower receiver. 
  • You want an 80% assembled lower receiver that comes with a jog. 

4. Black Rain Ordnance Stripped Upper & Lower Receiver

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The stripped upper & lower receiver features a Gen I pattern that is said to also accept the DPMS LR 308 pattern components, meaning it is able to accommodate the installation of a variety of aftermarket parts. And since it features the DPMS pattern components, this upper & lower receiver set is able to also take on the highly sought-after Magpul PMAG .308 magazine. 

In terms of construction, this upper and lower .308 AR platform set is fully machined from 7075 T6 aluminum material and is matched to produce an ultra-stable, full contact fit and finish without any occurrences of slops and rattles. The 7075 T7 aluminum material is also known to be very solid with very good corrosion resistance, contributing to the overall durability of the product. 

The upper receiver and lower receivers are available in either rugged, parkerized matte black finish, or non-guard electroless nickel finish that provides an impressive resistance to corrosion as well as surface wear. The assembly style is stripped AR with billet construction, since it is made from the billet method, this receiver might just be slightly more expensive compared to forged ones. 

Moreover, the bolt catch pin hole on this receiver set is even threaded without a forward assist so that owners won’t need to use a roll pin to secure both the stripped lower receiver and upper receiver together. In fact, you will only need to simply screw and unscrew the pin for added convenience. The AR-10 lower receiver is also equipped with an integrated trigger guard that’s handy to provide maximum structural rigidity. 

The pictogram selector markings on the .308 AR lower lets you select safe, fire, or 3-round burst firing position, depending on your personal preference. The visual aid from the pictograms elector is also a good idea as it lets you remember easily and view the selector any time. Meanwhile, the flattop upper receiver even includes a T-marked MIL-STD 1913 Picatinny rail for you to attach your favorite accessories. 

You would like this if:

  • You want lower receivers machined from 7075 T6 billet aluminum
  • You want lower receivers that accept DPMS type LR308 components
  • You want threaded bolt catch pin hole
  • You want a lower receiver with an integrated trigger guard
  • You prefer pictogram selector markings 

SHOP NOW

5. Cross Machine Tool Billet Receivers (Upper and Lower)

The Cross Machine Tool is a two-in-one assembly set that includes both the upper and receiver .308 AR set. In terms of construction, the receiver is said to be solidly machined from 7075-T6 billet aluminum material that enhances its strength as well as corrosion resistance, to further improve its durability. 

Compared to 6061 aluminum alloy, the 7075 T6 aluminum is referred to as one of the strongest alloys available thanks to its enhanced strength and high strength-to-weight ratio that is very crucial for the lower receiver to handle the powerful recoil from the firearm. Moreover, the receiver even comes with a matte finish and is hard coat anodized for a rather rugged appearance. 

As for the battle rifle build, this cross-machine tool upper and lower receiver set utilize the standard DPMS pattern and components which consists of the bolt carrier groups, charging handle, .308 lower parts, and dust cover. The AR-10 upper receiver also fits the DPMS high profile .308 style handguards, so you should know how important it is to get the right parts to assemble on the receiver for a tight and secure fit.

The AR receiver set also comes with an upper tension screw that is built into the lower receiver to ensure a quick and easy tightening process. While the fit might be a little loose, you can always make modifications from top to bottom to rectify the problem. You should make sure that both the upper and lower receivers are tightly secured with each other to improve the accuracy of your shot. 

The bottom line is that the receiver also has an ultra-flared mag well that is wire EDM cut in order to accommodate PMAG magazines. Last but not least, this upper and lower receiver set includes a takedown pin detent spring retention screw with mil-spec tolerances. 

You would like this if:

  • You want a receiver made from 7075 T6 aluminum
  • You want a receiver with a hard coat anodized finish

You might not like this if:

  • You want a lower receiver that utilizes DPMS pattern parts
  • You prefer an ultra-flared mag well
  • You want to use Hex head screw instead of roll pins

Conclusion

Your AR-10 rifle should be durable and tough enough to withstand the heavy .308 caliber that it fires. While the forged metal is generally considered superior to billet metal, it does not really make a difference with the AR-10 rifle. The DPMS platform is also a more versatile option with much more aftermarket parts available compared to the AR-style platform. 

Additionally, the lower receiver parts of the AR-10 and AR-15 are not interchangeable, except for the trigger and trigger spring. This is simply due to the size and caliber differences. 

You should also remember that buying a complete lower will require an FFL license, but you can opt to get an 80% lower and finish it yourself. However, ready-made lowers will definitely save you time and effort while offering quality machining and warranty coverage. 

Regardless of which type of lower receiver you choose, above are the best AR-10 lower receivers available that you can get your hands on now. We hope that today’s guide has given you enough information and comparison reviews to make a better purchasing decision on the best AR-10 lower model which will be the best fit for you. 

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