Choosing the right AR upper could me the difference between spending a lot of money on a upper the doesn’t serve you or worse…
Having it fail you when you need it most.
Lucky our collective 50 years of field experience went into making this article. You’re in good hands.
The Best Complete AR-15 Uppers
Aero Precision M4E1
Aero Precision is the most popular AR producer of the last decade. Why? Because they produce what you want at a low price. Custom Rails like POF-USA with a high level of quality control. The M4E1 has everything that everyone wants in an entry level AR build, free float rail, which is lightweight and uses the news designs choices like Picatinny rails for the sights but a slim line M-Lok rail for the rest. A high quality barrel that will shoot close to 1 MOA. Great customer service and solid brand recognition for resell value.
M4E1 is the go-to for most AR builders; their biggest problem is they can’t seem to keep them on the shelves. If you can find an Aero Precision M4E1 grab a couple and trade them with your friends. They will thank you.
PSA 16 CHF
The PSA CHF upper is a classic. The barrel is Cold Hammer Forged (CHF) by FN and will shoot great groups at a low cost, picking your upper will come down to barrel length and handguard choice.
A 16 inch is the shortest standard barrel, perfect for shooting out to 600 yards. The 18” and 20” barrels are great for longer distances or dedicated tack drivers but the choice is less about function than about ascetics and felt recoil. A 16 inch rifle is perfect for most situations, not to mention cheaper and more customizable, it will also be lighter. A 20 inch barrel is mostly made for rebuilding the Classics like a M16A2 or M16A4 for service rifle competition or making a varmint hunting rifle. The 18 Inch is for building a DMR rifle, the gain isn’t much but that isn’t the point. The point is that you build your own rifle.
Choosing a handguard rail is going to come down to length. PSA lightweight handguards are great for the price, 13.5, 15, or 17Inch handguards are all free float and can easily be changed out when you want to upgrade your rifle a bit, but it will be a hard look because they are everything you want in an AR-15 handguard.
Just make sure you grab a BCG and Charging handle if yours doesn’t include one.
POF USA Renegade+ & P415 Edge
If you read the best rifle article, you know I love everything about Patriot Ordnance Factory. Their rifles should be considered the standard for improved AR-15s and they are, unfortunately price can get in the way of what we want or in my case I own the P415 and want to grab a direct impingement just to see if there is a difference.
POF makes parts for GAP Precision rifles one of the premier custom rifle companies in the US and The Renegade and 415 show just what they can do with a rifle. For starters unlike nearly every other AR in existence POF uses a straight gas tube to prevent hot spots in their gas system making it as smooth as a baby to shoot. They use an oversized heatsink on the barrel nut to lower the temperature variances while shooting; this increases accuracy and prolongs barrel life. The dictator adjustable gas system to fine tune the blow back of the gas system, allowing for better suppressed fire or decreasing the gas system to the ammunition. They use a roller cam pin that reduces friction of the BCG. Perhaps the most innovative change is the E2 cutouts for bullet extraction. Tiny cuts allow the casing to eject easier decreasing the chance of a stuck casing wrecking your day at the range or fouling up in a firefight.
Those are only some of the innovations that make POF the best ARs and being able to buy a completed upper would make POF our best Complete upper if not for the fact that their innovative lower eclipses nearly every other lower on the market giving an AR that weighs only 7lbs. Perfect for Hunting, 3-Gun or a duty rifle. Be sure to check them out, then your bank account and credit score.
Daniel Defense is not as innovative as POF, instead they took the standard AR and refined process of manufacturing until they had one of the best rifles on the market. This Optics Planet exclusive has a 14.5in pinned and welded barrel, meaning you can’t change the flash hider without drilling and re-welding the flash hider. While most would consider that a downside DD guns are widely known as reliable, accurate rifles. Everyone that sees it will know it is a Daniel Defense rifle just by the color and the handguard. DD makes solid choices on handguards and barrels, they know what shooters want because they shoot themselves, and if you want an amazing rifle grab this upper.
Unfortunately, it costs about the same as the POF but lacks the innovations.
If you want a 16inch check out
ArmaLite M15 Tactical
ArmaLite is the one that started it all with the AR-15 in the 1960s and if Eugene Stoner could see what his rifle could do now I’m sure he would crack a smile. The M15 follows the best practices of every rifle on the list. A solid Barrel, free float the handguard, and use a recoil reduction flash hider and man did they succeed. The last time I took an ArmaLite to the Range I plugged 30 rounds into an 8 inch steel plate like a metronome at 200 yards using only a Burris AR-536 and XM193. If you think this is an easy feat on a cold rainy day, try getting off the bench to shoot. The ArmaLite M15 is just a solid rifle; unfortunately, there are better options in 2021.
Midwest Industries makes some of the best free float handguards in the industry and what they did building a complete upper is perfection. The only problem is that Aero Precision got there first.
After 60 years of producing the AR-15, you would think Colt would have most of the kinks worked out and they do, but they haven’t been able to innovate while producing rifles for the US military. If you want a Colt grab this one it’s their best work without visiting the Colt Custom Shop.
What you actually need to know
The barrel is the single most important aspect for mechanical accuracy in a firearm. You can attach a solid action and barrel to a 2×4 with a scope and still shoot a milk jug at a mile accurately. Your barrel is one of the most important factors you can control, but how do you know which barrel to purchase without looking through a massive amount of review sites. You buy a quality brand that stands behind their product Larue, FN, Aero Precision find a brand that supports you as a shooter and you will get a solid barrel. Keep on this list and you should be able to build a 1 moa rifle if you are shooting quality ammo Federal Gold Medal Match or Blackhills.
It is 2021 it is time to get into a free floated AR-15. A free floated barrel allows you, the shooter, to smash, twist it, pull it and pound on your handguard without affecting the accuracy of your rifle.
Rails come in many different options but the most common are M-Lok, made by Magpul for their metal rail systems, Quad Picatinny, Picatinny is the most common attachment system for AR-15s but it is showing its age, and Keymod, a solid system that lost out to M-Lok for use in the military. When looking at the rail systems choose M-Lok or Picatinny for longevity. Keymod will be phased out over time. It will become difficult to find components and attachments using the system requiring adaptors. M-Lok or Modular Lock works much better than Picatinny or KeyMod for polymer attachments, the ease of use and the free license made it the obvious choice for handguard rail replacement over Picatinny, which struggles with attachments.
The Gas System of the Ar-15 is direct impingement, the gas directly pushes on Bolt Carrier group to eject a spent round. While some companies such as POF-USA have created a gas piston system for the AR-15 most use direct impingement or DI. DI comes in several lengths pistol for less than 10” barrels, carbine for barrels longer than 9.75”, mid for 11.75” and above and rifle for 15.125”. Carbine and Rifle length have been the go to lengths for years but the Mid length gas tubes are becoming standard for 16” barrels. What does it change? Not much, but you need to match your gas system to your barrel and your buffer for reliability, accuracy and recoil. Generally don’t worry about it unless you are building your own upper, but if you can choose find the longest tube you can for the decrease in felt recoil.
Bolt Carrier Group/Charging Handle
Many uppers come without a charging handle and a BCG or Bolt Carrier Group, The Charging handle is a matter of taste many prefer slightly larger charging handles for a better grip or ambidextrous charging handles for the ease of use, but most start with the standard mil-spec. The BCG is another part that can be wildly expensive without much benefit, find a Full-Auto; no it has nothing to do with the guns rate of fire, and Magnetic Particle inspected or MPI.
If you need a BCG and Carrier handle grab this deal and get 10 free PMags.
POF-USA makes several of our favorite rifles check out the Strike Eagle and the Tomahawk for great charging handles.
The CMMG 22lr conversation kit allows you to turn most AR-15s into 22lr trainers. Perfect for new shooters and first time gun owners looking to shoot more for less. You will need a 5.56 BCG for shooting 5.56/.223 but it is a great accessory for training.
AR-15 caliber is 5.56 or .223, however because of the nature of multicaliber lowers, that same lower can be used with many different uppers. AR-10s are made for 308 but can also be used to shoot 6.5 or 450 Raptor even 350 Legend. When buying an upper make sure your lower will work with the caliber of your upper.
The Shit That Doesn’t Matter As Much
There are hundreds of different features that are nice for the seasoned shooter but don’t matter as much for most people. Often they are selling features that don’t change anything about the gun or are easily changed with aftermarket products. (1)
Feed ramps are essential for the reliable operation of your AR-15. Most AR-15s use M4 feed ramps or M16 feed ramps. M4 ramps are slightly more reliable but as long as you don’t cross your upper and barrel ramps it barely matters.
Monolithic uppers have a continuous upper Picatinny rail. 99% of people won’t use the two slots blocked by an upper and handrail so while it is a nice feature, don’t buy a rifle because it uses a monolithic rail system. (2)
Flash Hiders are one of the most changeable components on an AR-15. Look for the words Pinned and Welded on 14inch barrels because otherwise the flash hider just screws on and off like a nut on a bolt.
Back Up Sights
Unless you are using an A2 Carry Handle for your upper, most backup Iron Sights are just attached with an Allen wrench. They can cost around $50-$100 and are easy to change out.
Best AR-15 Stripped Lower Brands of 2023
If you’re looking for more on AR parts, we’d suggest reading our article on the best AR-15 stripped lower brands of 2023.
Best Direct Impingement AR 15 Rifles
If you just want gun suggestions, check out: best direct impingement AR 15 rifles.
- Jon Stokes, Why millions of Americans — including me — own the AR-15. Retrieved from https://www.vox.com/2016/6/20/11975850/ar-15-owner-orlando
- Annette Doerr, WHAT IS AN UPPER RECEIVER. Retrieved from https://www.guns.com/news/what-is-upper-receiver
Andrew Maurer is a Precision Rifle Series competition shooter and gunsmith and has been building competition rifles for over 12 years. He works as a big game hunting guide in Iowa, South Dakota, and Arizona. He is also a political scientist studying the effects of gun control on society. He teaches youth rifle shooting.
📧 Reach me via email at: Andrew@barrettrifles.com