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So you decided to buy an AR-15 upper receiver. Maybe you're just getting into the AR-15 market trying to make your current AR even better.
Either way, this article will help you find the best upper receiver on the market. Not just the best on the market either, the best for YOU.
At a Glance: Our Top Picks for Ar-15 Complete Upper Receivers
- OUR TOP PICK: Aero Precision M4E1
- RUNNER-UP: Bravo Company AR-15/M4 Complete Upper Receiver Assembly
- BEST BUDGET OPTION: PSA 10.5" 5.56 NATO 1/7
Comparison of the Best AR-15 Complete Upper Receivers
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What is an Upper Receiver and What Makes it Complete?
There are pretty much two parts to a full AR-15: a complete upper receiver assembly and a complete lower receiver assembly. Put those two together with some takedown pins, and presto – you have a finished gun.
What you'll be learning about in this article are COMPLETE upper receivers. While they don’t make up the whole of the AR's upper part, they have some key components. You'll find the following in a complete upper receiver:
- Bolt Carrier Group
- Charging Handle
- Barrel
- Forend
All of these together make for a complete upper receiver. A complete upper receiver alone does not an AR-15 make, but you’ll be close.
Aero Precision M4E1
What Should I Look For When Buying a Complete Upper Receiver?
There are a lot of different ARs out there and a lot of things that you as a potential AR owner need to know. Doing the most research possible is always recommended, but there are some things that you should look for immediately:
Barrel
Arguably the most important thing to keep in mind when choosing the right complete upper receiver is the barrel because it's going to be the determining factor in whether or not your rifle shoots accurately. Two things to look for: 11595E Barrel Steel (or 4150 steel) and whether or not the barrel is chrome lined.
Are the Bolt and Barrel High Pressure Tested? Was a Magnetic Particle Inspection Done on Them as Well?
These two processes are the bread and butter for a bolt and barrel testing. For those who are unaware, High-Pressure Testing and Magnetic Particle Inspection essentially mean that the manufacturer has fired a proof load through the bolt and barrel to attempt to find some weaknesses in the parts. Some manufacturers do this on every gun. Some do it on some, and others don't do it at all. Try to look for an upper receiver that's been through HPT and MPI to make certain your gun won't fail easily.
Forged Upper Receivers
Finally, when deciding on your upper receiver, try to look for one that is forged. These will be the strongest of the upper receivers.
Review of the Best AR-15 Complete Upper Receivers
And now, the moment you’ve all been waiting for– here are the best AR-15 Upper Receivers that we could find.
Best Overall:
Aero Precision M4E1
Pros
Cons
What Recent Buyers Report
The consensus from recent buyers is they cannot believe the quality of the upper receiver for the price they paid. They mostly love the fit and finish, they find the accuracy to be top-notch, and they all believe that Aero is going to be a major contender in the gun game very soon.
Why it Stands Out to Us
We can't help but agree with buyers about Aero– these guys never disappoint. And the M4E1 Upper receiver is no exception. This product is one of the best upper receivers on the market today. What stands out to us, like for most buyers, was the fit and finish. There were zero problems with the lower and the rest of the AR components. Not to mention the accuracy is phenomenal. This product is one of the easiest uppers to assemble. It has a solid rail, and it's lightweight, solid, and great for the price. Need we go further?
Bottom Line
Essentially, if you're looking for a top-quality upper receiver for a great price, look no further than the Aero Precision M4E1. Sure, the large handguard might not be what you're looking for, but everything else about it is just phenomenal.
Runner-up:
Bravo Company AR-15/M4 Complete Upper Receiver Assembly
Pros
Cons
What Recent Buyers Report
One thing that all buyers seem to agree on is that this receiver has one of the best fits out there. Just apply a little bit of heat to the receiver and presto, the barrel will slide right in and stay there. Probably one of the best fits on the market.
Why it Stands Out to Us
In our opinion, this is one of the best receivers for a custom build. If you want a receiver that fits on pretty much any gun you decide to use it on, then the Bravo Company AR-15/M4 Complete Upper Receiver Assembly is the right upper receiver for you. This upper is for the enthusiast who cares about accuracy and keeping their gun together. Not only that, but the price is great as well. All in all, this is a great upper receiver and should not be discounted because it's number two.
Bottom Line
Here's the bottom line about the Bravo Company AR-15/M4 Complete Upper Receiver Assembly: it's one of the best fits on the market, but be careful because sometimes your receiver may come with some blemishes. If you don't care about cosmetics, however, this is a great receiver.
Best for the Money:
PSA 10.5" 5.56 NATO 1/7
Pros
Cons
What Recent Buyers Report
Everyone seems to love this upper, and one thing they can all agree on is for the price, this is one of the best uppers on the market. This one uses some of the best materials out there. Plus, it shoots accurately, and it's affordable for any enthusiast out there.
Why it Stands Out to Us
We can't help but agree with the recent buyers here. This upper is one of the best-priced products out there, especially because it's forged with a 4150V Chrome-moly vanadium steel barrel. Seriously, if you're looking for an upper that's fairly priced with some of the best materials used in its construction, then this is upper for you. Great accuracy, stellar reviews from recent buyers, and in the end, a great addition to any AR that you're thinking of completing. It's just a blast to shoot as well. You can't go wrong with this one!
Bottom Line
The bottom line is this: if you're looking for a great price, look no further than this upper. However, keep in mind that you may have a hard time tracking your purchase, and you may not get everything that you paid for.
4. TRYBE Defense AR-15 16in
Pros
Cons
What Recent Buyers Report
People seem to love the price of this upper. There are a lot of reported problems with it, however, like the fit being not great and the BCG being low quality. There have also been reports that some have come with a blem chamber/barrel. However, that last point is cosmetic only.
Why it Stands Out to Us
This upper is a bit of a tough one to pin down. There's no doubt that this upper is well priced. No doubt at all. However, you might have to do some shaving down or shaping to get your upper to fit, and that's not something any enthusiast wants to do. You don't want to destroy the integrity of your upper. Plus, the reports of blemishes on the barrels and chambers are something that makes our collective chests pretty tight about this upper. And then, of course, with a cheaper upper comes a cheaper bolt carrier group, which is expected but not ideal.
Bottom Line
If you're looking for a well priced upper, this one is pretty good. But keep in mind the things you sacrifice when you buy something well-priced, most of all quality. Bottom line: buyer beware with the TRYBE Defense AR-15 16in Complete Upper M-LOK, .223 Wylde.
5. Daniel Defense DDM4 V7
Pros
Cons
What Recent Buyers Report
A lot of people have said a lot of different things about this upper. Some report that it has a flawless function, a lot more report on its flaws. QD attachment points are not milled out, they’re cheap charging handles– and for that price, those should not be.
Why it Stands Out to Us
Sure, there have been a lot of reported problems with this upper. Sure, the price is a little bit on the steeper side. But the outstanding thing about this upper is how lightweight it is. In fact, in our experience, it's probably one of the most lightweight uppers on the market. Also, one can't deny that Daniel Defense is one of the best manufacturers on the market. Could these bad reviews be from competing companies? What kind of conspiracy are we potentially dealing with? Who cares, all we know is that if you're looking for a lightweight upper, look no further.
Bottom Line
The bottom line is this– if you're looking for an AR pistol upper, then go with Daniel Defense. Sure, there have been reports of flaws, but you can't get any more lightweight than this upper. And at the end of the day, isn't that what you want?
AR-15 Upper Receiver Types
All right, now that you've seen the best, it's time to discuss some of the different types of AR uppers out there. There are only four different types of uppers in the world of ARs:
A1
Developed for soldiers in Vietnam, A1s have a fixed carry handle, forward assists, a light profile barrel, a flip rear sight, and short and long-range apertures. Accuracy: 450 yards.
A2
This is the upgraded version of the A1, and it also features a fixed carry handle and a forward assist. The A2 now has adjustable elevation up to 600 yards, as well as windage. It is also heavier than the A1.
A3
If you want to know an A3 receiver, look for its distinctive flat top configuration, as well as a detachable carrying handle. There are a lot of models out there with weaver rails, mostly for mounting scopes or other accessories. On A3s, you'll also find forward assists and rifle cuts in the feed ramp. Finally, you can get a higher scope positioning with the A3s high rise configuration.
A4
These are the most common uppers out there. The A4s are very similar to the A3s, but they have M4 style feed ramps.
And that's it! The names are pretty easy to remember, aren't they?
AR-15 Disassembly
Now, we're going to talk about AR-15 Upper Receiver Disassembly. This process is pretty simple; however, we want to make sure we describe it to the utmost detail. We don't want to leave any newer gun enthusiasts out of the loop.
Steps:
- Locate the takedown pins. Your upper receiver is attached to your lower receiver via two takedown pins. One in the front, one in the rear. Look for them, they should look like little buttons on your gun.
- Press down on both your takedown pins. Once you've located the button-like takedown pins, then press down on both of them. This action will allow your gun to come apart.
- Pull out both the takedown pins. Now that you've pressed down on the takedown pins, you should be able to pull them out until a certain point– they will stop. It is unlikely that you will be able to remove them completely.
- Separate the upper from the lower. After you've pulled out your takedown pins, then you should be able to separate the lower from the upper pretty easily.
And that's about all there is to disassembling an upper receiver! Be sure to refer to the video below for a full overview of what we described.
How to Assemble an AR-15 Upper
Now we're going to talk about installing your upper receiver.
Tools
When it comes to tools you need, the bare minimum is an upper receiver vice block, a vice, and a barrel nut torque wrench. If you have this, you should be ready to go.
- Secure the upper receiver. Secure your upper receiver to your vice.
- Inspect. There are a lot of things you have to look at– check the threads of your upper receiver. Check the gas port for obstructions.
- Slide the barrel into the upper receiver. Some barrels may be a tight fit, but others may not. For the not so tight, consider a thin coating of blue Loctite.
- The barrel nut. It's going to get pretty complicated now, but this is the most important part. The barrel nut installation will depend on the handguard you have purchased– some may attach with threads, some may attach with hex screws, some may attach with adhesives. However, you must always thread the barrel nut onto the upper threads. Afterward, you must place your barrel nut wrench into the gas tube holes. Then, use the torque wrench on the barrel nut wrench. The torque should be around the 30-65 lbs. range. Start at 30lbs, and continue torquing until you have the perfect alignment. This process takes time.
- Installing the gas block, gas tube, and handguard. Lightly tap the gas block roll pin into the gas tube. Slide the gas block onto the barrel, then insert the gas tube into the upper receiver. Then, tighten the gas block screws after installation. Install your handguard with the provided attachment.
- The Charging Handle and the BCG. First off, place your charging handle into and past the indents, and then put the BCG into the upper receiver afterward.
And that's it!
Conclusion
And that’s all you need to know about complete AR upper receivers. We gave you a lot of information, and between that and our recommendation, we hope you found the perfect one for you.
People Also Ask
Do you still have questions? Good, because we still have some answers. Here are some of the most common things people ask about AP uppers.
What Does a Complete AR Upper Come With?
As previously mentioned, a complete upper receiver will come with The Bolt Carrier Group, The Charging Handle, The Barrel, and The Forend. Some may also come with an ejection port door, the forward assist button. There are also packages called "complete upper receiver assemblies", which are pretty much the entire top half of the gun.
How Long is an AR Upper Receiver?
AR Upper Receivers come in a variety of different sizes, but keep in mind for your AR to be legal (at least in the United States), you need to have at least a 16-inch barrel length. And legality should probably be your top priority when it comes to purchasing a gun.
How Far Does the Gas Tube go Into the Upper Receiver?
The incredibly short answer to this question is about six inches. There is a hole at the front of the upper receiver (where the tube goes into the barrel). From that point to the port on the barrel is about six inches. However, different guns may vary, so don't take this as gospel.