Because it’s a high wear part, getting one of the best AR-15 Upper receivers you can afford is important… But they aren’t expensive. In fact, one of my favorite uppers is very affordable.
You don’t need to spend an arm and a leg to get a great upper receiver.
You can spend a LOT for something with all the bells and whistles, but for a range gun you don’t need to. Most people just need a good mil-spec upper anyway. But I included some options below for those who like going the extra mile in their AR-15 builds.
The one thing you want to avoid at all costs is something cheaply made. I made that mistake when I built my first AR-15 and ended up with a terrible upper receiver (made by SAA = stay away) .
I won’t make that mistake again.
(NOTE: This article is part of my "Best in Class" series where I list the top choices for various parts of your AR-15. You can find the other parts here: Best in Class Articles.)
FYI: If you buy after clicking most of the product links on this page, I'll make a few pennies out of each dollar you spend. It's not much, but it keeps the website going and I would appreciate your support. 🙂
Gibbz Arms G4 Side Charging Upper Receiver – $240
I’ve sunk about $2400 into my personal AR-15 and I currently use the WMD Nickel Boron upper (covered below). But if I was doing it over again I’d use the Gibbz Side-charging upper because the advantages of left side charging are HUGE.
For starters, to charge a standard AR-15 requires moving your head from the stock or un-shouldering the weapon. (Unless you want to hit yourself in the face.)
Second, when you have a scope mounted getting to your charging handle can be a slightly awkward. I do list several that deal with this issue in my best AR-15 charging handles article.
Third, it’s a real pain to get the bolt locked back without using two hands and unsholdering the weapon. It’s doable and made easier with things like the Magpul BAD lever, but not easy.
None of those are deal breakers, but they are annoying.
However, the biggest issue with the standard AR-15 charging handle is it’s just not ergonomic.

Picture Credit here
For a right handed shooter (most of us) it’s simply better and faster to use our support hand to charge a weapon.
That’s where the Gibbz Side-charging upper comes into play. It adds a left side charging handle to your upper receiver. The upper itself is made from 6061 Aluminum and Type III class 2 hard coat anodized per Mil–A-8625.
You can find a complete review here, I’m just going to hit the highlights.
It’s non-reciprocating (meaning it doesn’t move with the bolt) and provides an easy way to charge your AR-15 from the left side. When the bolt locks back, an integral detent holds the charging handle so it won’t slide around.
The best part: It doesn’t require a proprietary bolt carrier group.
Many of the other side charging upper require that you use their own BCG to function properly. Not the Gibbz, just swap out your BCG’s cam pin for the one that comes with the upper and voila! You’re ready to go.
It’s a great functional upgrade, plus you’ll save you $50-$90 bucks buying a high-quality charging handle.
Speaking of, there’s a small, spring-loaded door at the rear of the upper where the old charging handle used to be. the door keeps dirt and debris while still making it easy to disassemble and reassemble the weapon.
WMD Guns NiB-X Upper receiver w/Black Topcoat – $143
The WMD Guns Nib-X Upper receiver is the current upper on my ~$2400 AR-15.
WMD guns makes these upper receivers from forged 7075-T6 Aluminum (which is ideal). However the best thing about this upper isn’t what material they used to make it, but how they finished it.
It is plated inside and out with WMD’s proprietary “NiB-X” coating, which is an improved version of standard Nickel Boron coating. After plating, they give it a black topcoat on the outside only for color.
The advantage of Nib-X is the wear characteristics.
For starters, Nib-X is very hard. It takes forever to wear out because it has a Rockwell hardness of about 70. For comparison, that’s a harder than Chrome plating.
Second is how slick it is. NiB-X has a Coefficient of Friction around 0.06. For some scale, Teflon is about 0.04. This slickness (technically called “lubricity”) means a smoother action and stuff just doesn’t stick to it. Like Teflon, it’s incredible easy to clean. I’ve cleaned Nickel Boron plated AR-15 Bolts with just a dry paper towel and my fingers before.
The third is corrosion resistance. While nothing is corrosion proof, NiB-X is more corrosion resistant than Chrome plating.
Those features mean a few things:
- Reliable, even with very little oil. No gun should be run dry, but NiB-X will tolerate low/no oil longer than most.
- Smooth, the hardness and slickness makes for a very smooth action. (My AR-15 is the smoothest I’ve ever felt.)
- Easy to clean, Mostly it just wipes clean.
I’ll say right up front that Nib-X might be overkill on the upper receiver. The standard type III hard coat anodizing is a great finish and has worked well for over half a century. Do you need NiB-X? No. But it’s a great choice if you want to go that extra mile in a high quality build.
Aero Precision AR-15 Upper Receiver – $85 Stripped – $100 Assembled
I won’t say a lot about this one other than it’s a VERY high quality AR-15 upper receiver that’s made and finished correctly.
You can buy the Aero Precision upper in a Stripped Version with no upper parts or a Complete Version which has the parts kit already installed.
Aero Precision makes these from forged 7075-T6 aluminum and finishes them with MIL-8625 Type 3 Class 2 Hard coat anodizing. The military requires that specific material and finish because they have both worked very well for over half a century.
This is probably the best option for most people. Unless you’re looking for something special, this is a workhorse upper receiver that would make an excellent foundation for any AR-15 upper.
Best AR-15 Upper Receivers Conclusion
An AR-15 upper receiver is one the most important and most overlooked parts of the rifle. You NEED to have a quality one, but that’s about it.
I love the feel of left side charging, so I would go with the Gibbz on a higher-end build. (I plan on upgrading my AR-15 with one when I get the time/money) The WMD guns Nib-X upper is great if you want to make cleaning easier.
Personally, I think most of my readers will be best served with the Aero Precision Upper. It’s a solid, high-quality and properly finished part at a good price. I’m sure there’s plenty of other Uppers that fit that description, but I know Aero Precision makes their uppers correctly.
That’s why I recommend them.
(Remember this article is about the best AR-15 upper receivers, not the cheapest upper receivers.)
Any comments on Anderson lowers? They cost less than Aero. What are the differences vs Aero for the money?
The lowers should be perfectly fine because they don’t take nearly as much wear as the uppers. Until very recently, I thought the Anderson uppers were just as good as Aero. But since starting this website I’ve talked with a few people who had issues. It’s all second hand though, so I’m not 100% sure. With Aero Precision, I am 100% sure they are made correctly and that’s why I recommend them.
Anderson are good multi caliber lowers. Not to up to date with the other brand. But I own 2 Anderson lowers(sad to say none of them have the RF85 treatment) I know it’s not a big deal nor is it a performance enhancer. That said A buddy of mine has a Anderson RF85 it won’t take on fingerprints, dirt and all the extra shit left wipes clean off with water and soap. I envy him due to the fact he pays nothing for clean stuff. Don’t rule them out and if you can do the safe thing by them both😁
If you like the Gibbz, another consideration should be Roush Sports gen 2 side charger. It does away with the flat metal “door” that slides directly back and towards your face when charging the rifle. Instead it uses a captured and sprung setup that works as well, but without having to protrude out the back when in use. https://rouschsports.com/shop/ar15-upper-parts/side-charging-non-reciprocating-upper-receiver-newest-and-best-available/
Any comment on the Spike’s Tactical receivers? I have one for my lower and was planning on getting the upper to match (was told many times if from the same manufacturer the fitment is better).
Any in-spec lower should work fine. Getting a matched set often means a better fit, but getting them from the same company doesn’t guarantee a better fit. I prefer forged receivers because they are stronger, but the difference is basically moot unless you use it as an (expensive) club.
Any comments on a full upper assembly and barrel for the 6.5 grendel? Lot of companys out there selling em. Who makes a good one with out breaking the bank?
To be honest, I’m not sure because I’ve literally never bought an assembled AR-15 upper (or lower). And you weren’t kidding about there being a lot of options. A quick Google search turned up this thread on the MSRHunt forum which has a list of people selling them. I hope that helps.
I’ve built several AR’s on Anderson uppers/lowers.
I find the fit and finish to be very good.
Quality to be quite acceptable and the price exceptional.
I can’t imagine spending $2400 to build an AR!
I try desperately to keep my builds under $700! LOL!
I recently found a brand spanking new AR at Atwoods for $399.99!
That’s tough to beat!
My AR build last year was on Anderson lower and upper. Fit was very good and all the internal parts fit where they should with very little filing. My current build is on Aero Precision lower and upper. the fit together is just a bit off in one spot. They are still very good in my mind. they are also fitting the rest of the pieces just fine so far.
My FFL buddy contacted me when he saw a sale on the Aero Precision upper and lower. I snagged them right up. $100 for both pieces was awesome for me. I don’t benchrest with an AR, I hunt with them. I do spend alot of time at the range though. I like to shoot. Keeping my loads fine tuned to the gun is important to me. I like to hit what I aim at. Besides, shooting is just plain enjoyable!!
Vltor Mur 1A & 1S are the best forged uppers period. It’s disapointing that thes weren’t mentioned. And they are in stock at Brownells.
The Mur 1S (no forward assist) is what I’m running in my $2400ish Ar 15
Something I found recently that looks pretty darn terrific is the Aero Precision M4-E1 (threaded). I got the lower in FDE but couldn’t find a matching M4-E1 upper but it looks really darn sharp. I know the lower is just beautiful. When I can get one I’ll have to decide if my .223 or my 6.5 Grendel upper needs it and I’ll adjust the non-E1 upper accordingly. Try the Aero M4-E1 combo on your next build. I don’t know if it’s the best but it’s pretty sleek.
Ps, Also cool is the screw, not roll pin, Aero includes for the bolt release and the trigger guard is molded into the body and has downward bend in it so it ends up being the rough equivalent of the Magpul trigger guard.
Argh! That’s on the lower obviously. But create a terrific overall effect if you use the matched set.