At a Glance: The Best AR-10 Upper Receiver
Comparison of The Best AR-10 Upper Receiver
Our Top Pick
|PSAGen3 PA65 20″ Rifle-Length 6.5 Creedmoor M-Lok Upper||View Latest Price|
Our Top Pick
|Aero Precision 308 AR M5 Upper Receiver Stripped||View Latest Price|
Our Top Pick
|PSA Gen3 PA10 18″ .308 WIN M-Lok Upper||View Latest Price|
Custom building an AR-10 from scratch is one of the most enjoyable experiences that I’ve had in all of my years as a gun owner. I meticulously hand-selected every piece of my build for optimal performance and function. I knew then and know now that quality receivers are the cornerstones of any AR build, which is why I made sure I picked the best AR-10 upper receiver I could find.
Our Guide to The 6 Best AR-10 Uppers
Picking an AR-10 upper for your build sounds simple enough in theory. However, the market is filled with dozens of upper receivers. Unfortunately, there are some pretenders in the bunch that can derail your build and leaves you disappointed with, if not outright frustrated about, the final product. That is why we have narrowed your search down to 6 high-quality AR-10 upper receivers to help you complete your build.
PSAGen3 PA65 20″ Rifle-Length 6.5 Creedmoor M-Lok Upper
We will kick off our review with the PSA Gen3 PA65 complete upper receiver chambered in 6.5 Creedmoor. This receiver includes the charging handle and bolt carrier group, as well as a heavy profile 20″ stainless steel barrel. It comes standard with a free-float M-Lok rail and partial Picatinny rail across the top of the receiver. The flash hider is also included.
The PSA Gen3 is a high-quality upper receiver and is a great option if you are looking to upgrade the factory upper of your AR-10 or are completing a new build. Installation is a breeze with a compatible lower receiver. If this is your first AR10 build, you should keep in mind that parts are not as universally compatible as they are with the AR-15.
As mentioned above, this PSA Gen3 complete upper is chambered in 6.5 Creedmoor, not .308. That is not a problem if 6.5 Creedmoor is the desired caliber. This upper follows the DPMS AR-10 pattern and is compatible with DPMS patterned AR-10 lower receivers, allowing you to convert your rifle that fires .308 to 6.5 Creedmoor by simply swapping out upper receivers. Just make sure you load the right ammunition to avoid a costly and potentially dangerous, mistake.
If you are looking for a good quality upper receiver and aren’t concerned about getting to handpick every part of your build, this PSA upper is a solid choice. It will allow for the addition of attachments and you can always reconfigure it later if you decide you want to make further adjustments.
- Complete Upper Receiver
- BCG included
- Thick contoured, durable barrel
- DPMS cut
- Somewhat heavy
- One finish option
Aero Precision 308 AR M5 Upper Receiver Stripped
Our next choice is the M5 stripped upper receiver manufactured by Aero Precision. This AR-10 upper receiver is made from forged aluminum and features a matte black anodized finish, resulting in an extremely durable and wear resistant upper receiver for your build. It also has a Picatinny rail across the top of the receiver to allow for the attachment of an optic.
As mentioned above, this is a completely stripped upper, meaning that it does not include any accessory parts needed to complete your build. Your bolt carrier group, barrel, handguard, gas system, charging handle, and flash hider must be purchased separately. This is no big deal if you are looking to complete a custom build as you want to handpick all of your parts anyway and allows you to create a truly custom gun.
The M5 upper receiver is manufactured in a DPMS cut and is compatible with DPMS patterned lower receivers. I actually used this Aero Precision upper receiver for my last AR-10 build and had zero fitting issues with the lower receiver. The only special concern for this part is that you have to order Aero Precision’s takedown and pivot pin set because the pivot pin is longer than a standard-length pin. A longer anti-walk AR-10 pin should work as well.
- Forged aluminum
- DPMS cut
- Compatible with other DPMS lowers
- Extremely durable
- Picatinny rail
- Requires Aero Precision pivot pins
PSA Gen3 PA10 18″ .308 WIN M-Lok Upper
For our third pick, we will take a look at another PSA complete upper receiver. This receiver is chambered in .308 Win. Like its counterpart, the PSA Gen3 PA10 comes standard with the bolt carrier group, charging handle, flash hider, and barrel. This complete upper receiver sports an 18″ barrel with an “A2” profile, meaning it is slightly lighter and shorter than the PA65 listed above.
This upper receiver, like all PSA AR-10 parts, is manufactured in a DPMS cut. The DPMS pattern is the more popular and widely used of the two, but it is important to keep in mind that the ArmaLite pattern is still used by some manufactures and will not fit properly with DPMS cut receivers.
As long as your lower receiver is a DPMS cut, this upper will drop right in and be ready to go.
It has a five-position adjustable gas block to allow you to fine-tune your upper receiver for optimal performance, but it functions great right out of the box and didn’t require any adjustments for most users. A gas piston system would be a nice addition to allow for even better cycling and more exact adjustments. Regardless, the lighter weight and free-floating rail make for a very accurate rifle, capable of producing tight shot groupings on a consistent basis.
- Complete upper receiver
- Picatinny Rail
- Relatively lightweight
- One finish option
- No gas piston system
Brownells BRN 10 Upper Receiver Builder’s Set
Our fourth entry is a more nostalgic offering manufactured by Brownells. The BRN 10 Upper Receiver Builder’s Set is a retro build kit, featuring a classic upper receiver and sight set. It even includes the old-school three-pronged flash hider. It is available in three barrel lengths: 16″, 18″, or 20″.
The build kit includes all the hardware you need to complete the upper receiver except for the handguard and bolt carrier group, allowing for a good amount of customization while saving you the hassle of having to separately order some of the smaller parts like the slip-ring assembly. It is compatible with standard AR-10 bolt carrier groups and handguards.
It is important to note that this upper receiver is only compatible with the BRN 10 Lower Receiver build kit. That build kit, much like the upper build kit, includes the needed pins and fire-selector mechanism to complete your build but allows you to purchase more significant parts separately. That includes the trigger assembly, stock, and buffer tube.
This upper receiver kit simplifies the build process and will produce a high-quality rifle that performs like a champ when paired with a good barrel and bolt carrier group. The raised sights and fixed handle on the upper receiver are the only negatives about this rifle if you have an interest in installing a more advanced optic. But if you are interested in a classic look that delivers solid performance, then you can’t go wrong with the BRN 10 build kit.
- Includes most hardware
- Three different barrel lengths available
- Includes sights
- No Picatinny rail
- Handle/sights prevent mounting of scope/optic
- Only compatible with BRN 10 lower
Brownells .308 Upper Receiver 20″ Barrel with Front Sight
Next up is an Aero Precision M5 upper receiver paired with a Brownells 20″ barrel. This kit pairs Brownells lightweight .308 barrel with the superb durability offered by the forged aluminum M5 upper. The barrel includes the retro front sight but the Picatinny railing across the top of the upper receiver allows you to attach a flip-up style rear sight and an optic, giving you a secondary aiming option if your optic were to fail.
This kit also includes mounting hardware needed to attach a handguard. However, it does not include the charging handle, handguard, muzzle device, or bolt carrier group. If you are like me, you probably prefer to pick them out yourself anyway.
By swapping out the BRN 10 upper receiver in this build kit, Brownells increases your build options. The M5 upper receiver is compatible with all DPMS cut lower receivers, making it easier for you to find the parts you need to match the goals of your build.
Once you complete your AR build, you will be pleasantly surprised by the performance of this Brownell’s barrel and Aero upper. It produces tight shot groupings and offers consistent results. It is lighter than expected for a 20″ barrel, weighing in at only 2.5lbs.
- Barrel included
- Forged upper receiver
- Compatible with DPMS lower receivers
- BCG not included
- Only one barrel length option
- Only available in .308, not 6.5 Creedmoor
Knights Armament SR-25 Precision Rifle Complete Upper Receiver .308 Win
Our sixth and final entry is the SR-25 Precision Rifle complete upper receiver manufactured by Knights Armament. This is a true competition quality upper receiver designed for shooting from extreme distances.
Knights Armament lists this rifle as being accurate from ranges in excess of 1000 meters. While I didn’t get to test its performance at those ranges, I can confirm that it is a tack driver up to 500 yards, producing extremely tight groupings every time.
This upper receiver includes all necessary parts, including pop-up front and rear sights. It also has a full Picatinny rail across the top and M-Lok railing on the sides and bottom of the handguard for the addition of various attachments. It has a 20″ precision barrel with a mid-weight contour to provide a good balance of performance and weight.
The only real drawback of this upper receiver, and I am reaching here, is that it is not a DPMS cut. It is only compatible with SR-25 cut lower receivers and I would personally recommend sticking with Knights Armament’s lower receiver just to be on the safe side. While other SR-25 cut lower receivers would be compatible, I would avoid the unnecessary risk of diminishing the performance of this upper receiver.
- Supreme accuracy
- Complete upper receiver
- Pop-up sights included
- Full Picatinny rail
- M-Lok railing on handguard
- Only compatible with SR-25 lower
- Will not fit on DPMS pattern lower receivers
Guide to Upgrading Your AR-10 Upper Receiver
There are three main reasons that people buy AR-10 upper receivers.
- The first and perhaps the most prevalent reasons are to complete a custom build.
- The second is to replace a subpar or even damaged upper receiver with a new, more durable one.
- The third is to convert your AR-10 to a different caliber.
Regardless of your reasoning, choosing a quality upper receiver that improves your AR-10 and accommodates your goals as a shooter are important considerations when making your decision.
Building an AR-10 Rifle
If you have worked with the AR-15 family of rifles, you are accustomed to general parts interchangeability based on military specifications. The various manufacturers of .308 AR rifles had no such standard; they made changes to put their own brand on them. For a home-builder, it means you can’t buy parts without doing some homework. Building an AR-10 from scratch has a ton of great benefits when compared to simply buying a finished gun. I, for one, find myself much more invested in the experience and value the finished product more when I have chosen every part of the gun.
Choose the right Buffer and Spring Combination
One of the most appealing things about an AR-10 build is that you can reconfigure your gun for different purposes as your interests or preferences change. If you want to build a .308 AR choosing the right buffer and spring combination for your gun is the easiest way to make your gun run.
One of the most appealing things about an AR-10 build is that you can reconfigure your gun for different purposes as your interests or preferences change. Building an AR-10 from the ground up allows you to purchase a few tried and true parts from companies you trust while also giving you the flexibility to configure your rifle how you want and try out some new products while you’re at it.
Which buffer and spring should you use in your rifle?
That depends on your buffer tube, gas system length, the gas port size, ammunition, and if a suppressor will be utilized. I can recommend some solutions, but with all these variables, some experimentation is required. In fact, you might need more than one buffer and spring combination if you plan to change uppers or ammo.
I have seen many ARs of all calibers falter because of ammunition.
Many .308 ARs use an AR-15 buffer tube. Because the .308 AR requires longer bolt travel, you cannot use an AR-15 buffer in an AR-15 buffer tube on a 308 rifle. The careful balance of length of the carrier, the amount of travel required, the length of the buffer, and the compressed length of the buffer spring determines if and how well your rifle functions. Change any one factor and it can stop everything. There are several combinations that will work, the buffer can be shorter or the buffer tube can be lengthened. The spring selected must match.
I frequently tinker with my builds to make minor adjustments. This may be something as small as swapping out optics to something as involved as replacing the gas system and barrel. Custom builds allow you this kind of flexibility and it all starts with a quality upper and lower receiver.
Components to a Great Upper Receiver
When choosing an upper receiver for your AR-10, there are three main factors that should be taken into account before making your purchase.
- The method of manufacture and build material is vital because it will most directly affect weight and durability.
- The second is if it includes a Picatinny rail or instead has a carrying handle.
- The third is whether or not it is a finished or stripped upper receiver.
Upper Receiver Materials
Most receivers are manufactured from aluminum. However, polymer receivers are also available. Each has its benefits for certain applications, but there is always a give and take when it comes to weight and durability.
Polymer uppers can provide significant weight reduction and are often reinforced with metal at high-stress points. The trade-off with polymer uppers is that they provide substantially less strength and durability when compared to aluminum upper receivers. Our list does not feature any polymer uppers due to their durability concerns outweigh the benefit of a lighter weapons platform.
All of the uppers featured on our list are either billet aluminum or forged aluminum, both of which are great choices for your AR-10 build. Some upper receivers are manufactured using a casting method, but billet and forged receivers offer the best performance results.
Billet Upper Receiver
When a receiver is called a “billet” receiver, it just means that it was created from a single piece of stock material. This material is cut to an approximate size to create the upper receiver and is then machined from start to finish.
The machining process often requires that the upper be transferred from different machines during the process, taking longer than the creation of an upper from forged material. Billet uppers tend to be more unique because manufacturers often add extra material to stress points to improve durability.
Forged Upper Receiver
Forged uppers are made in a more drastic process. They are made by hammering raw aluminum into a rough shape close to that of the desired receiver. Once the forging process is complete, they are also finished with CNC machining devices to precise specifications. The forging process offers better durability than any other manufacturing process.
When it comes to picking between billet or forged receivers, it is generally a matter of preference.
The billet receiver will usually be a few ounces lighter and likely have a unique finish or design. Billet receivers have a precision fit when using a billet lower of the same brand because the parts are manufactured on the same machines.
However, the forged receiver is extremely durable and produces the best fit when mixing different brands of upper and lower receivers, as long as they both follow the DPMS cut.
The two primary designs for AR-10 upper receivers are receivers that feature:
- A carrying handle and,
- Receivers that have a Picatinny rail across the top.
Those featuring the carrying handle are great for completing a retro build and include the rear peep-hole sight.
With that in mind, the rounds available for an AR-10 are designed to let you reach out and touch your target from long distances. If your goal is optimal distance and accuracy, then the Picatinny rail is the way to go.
Complete Versus Stripped Upper?
When choosing between a complete or stripped upper receiver, it’s all about personal preference and your goals. Complete uppers get your gun up and running faster, but a stripped upper receiver provides more flexibility.
Complete Upper Receiver
A complete upper receiver is an excellent choice when you are seeking to convert your AR-10 from one caliber to another but still want to be able to quickly swap back in the future. The complete upper will have all the required hardware to make the change and get you out to the range quickly.
Complete upper receivers are also appealing if you have a finished AR and are just looking to upgrade your barrel and BCG in one easy swap.
Stripped Upper Reciever
If you already have a functioning rifle and have decided to undertake a build, then I would recommend a stripped upper receiver. If you are going with a billet option, your safest bet would be to purchase the same brand lower receiver to avoid fitting issues. Doing so will still allow you the flexibility to choose your barrel, bolt carrier group, and trigger, which are the drivers of your rifle’s performance anyway.
During my last build, I mixed and matched all the parts other than the receivers and ended up with one of the best performing guns to date.
If going for a build with a stripped upper receiver, you can order lower and upper parts kits that include all required hardware to complete your build. This includes the detents, pins, safety selector, and other small parts that will not have any substantial variations in quality as long as you purchase it from a reputable company.
If you are new to AR-10s or the AR market in general, then you may be surprised to know that you can convert your AR platform rifle to fire a different caliber than the standard. The standard caliber for the AR-15 is the .223/5.56 round and the standard for the AR-10 in .308 Win. A relatively new round that can be fired from your AR-10 and has been surging in popularity is the 6.5 Creedmoor.
The 6.5 Creedmoor is a great round that performs comparably to the .308 Win. However, it offers some advantages in long-distance shooting from about 800-1200 yards. Without getting too technical, the 6.5 Creedmoor experiences less bullet drop and maintains higher velocity at these distances when compared to a .308 Win round of equal quality.
Completing the conversion can be done in one of several ways.
- If you do not want to purchase a new upper receiver, then you can strip down your rifle and remove the handguard, barrel, gas system, and bolt carrier group.
- You can then install a 6.5 Creedmoor barrel and bolt carrier group and re-install the other parts to finish the conversion.
- To do this without buying a new gas system, the new barrel must be the same length as the original.
As you can see, this process can be a bit tedious and you are still having to replace the barrel and bolt carrier group, which are two of the most expensive parts of your rifle anyway.
The alternative is to purchase another upper receiver
Whether you purchase a finished upper chambered in 6.5 CM or a stripped upper and outfit it with a 6.5 CM barrel and BCG, you simply remove the .308 Win upper and install your new upper with the takedown and pivot pins to complete the conversion.
The second option is what I opted for, allowing me to quickly swap my rifle from .308 Win to 6.5 CM and back again if I want to. I usually make the swap before heading out to the range or the woods and carefully ensure that I’m only bringing the appropriate ammo with me to avoid any mishaps. I like to label my magazines with a permanent marker to make this easier but to each his own.
Forged to Perfection – Our Top Pick!
When it comes to quality guns, any successful build has to start with a good foundation.