The Best AR9 Uppers

There are plenty of benefits to converting your AR with a 9mm upper. The flexibility of PCCs has driven their popularity over the past 20 years, making them the go-to choice for those who want a multi-role pistol caliber rifle. With all the options and benefits of building a pistol-caliber carbine (PCC), it’s high time you get started.
Kenzie Fitzpatrick


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best ar9 uppers - cover

This article is part of our Guide to Everything AR

There are plenty of benefits to converting your AR with a 9mm upper receiver. The flexibility of PCCs has driven their popularity over the past 20 years, making them the go-to choice for those who want a multi-role pistol caliber rifle, and one of the main reasons I have one in my collection.

With all the options and benefits of building a pistol caliber carbine (PCC), it’s high time you get started.

In This Article:

AR9 Upper Receiver Comparison

Below is my list of the AR9 upper recommendations. I list the best choices in terms of value, performance, design, and cost.

Click on the name to head to the product page, read reviews and check prices or skip ahead to the list of upper receivers.

AR9 Upper Reviews

1. PSA Gen4 9mm Upper Receiver

best pistol caliber carbine - PSA AR-V Barrel Flash Can
The PSA Fluted Flash Can may not reduce the noise, but it certainly looks the part.

Palmetto State Armory (PSA) has recently hit the pistol caliber carbine market hard. Their products are always of high quality with a more modest price point.

The PSA PA-9 upper includes a Gen 4 hybrid 9mm bolt carrier group and charging handle, making this a competitive setup in one purchase. 

The barrel length is 10.5 inches, typical of a 9mm AR-15 upper but still considerably shorter than those used to a traditional 5.56/.223 rifle, which will generally see barrels in the neighborhood of 16 inches (or more). I find the 10.5-inch length to be a good middle-ground for mobility and accuracy.

I really liked the fit of the upper, barrel, and shroud. It feels like a much more expensive firearm when in-hand, although there's little room beneath the rail to actually mount anything, and the uber short barrel is screaming for a hand stop.
The 5-inch version of the Gen 4 PSA upper gives me SBR feels.

The PSA flash can is designed to direct gasses and noises forward away from the shooter because of the shorter length of this upper. This is great for keeping the shooter safe from hot gasses and helping minimize barrel rise. 

The last thing to note is the handguard is M-Lok, so be sure any attachments added to the handguard are compatible before purchasing. I tend to run M-Lok with both PCC and AR builds, which prevents me from shelling out for accessories twice.

Shooting 9mm rounds with the PSA PA9 PCC fitted with their AR9 upper.
Shooting 9mm rounds with the PSA PA9 PCC fitted with their AR9 upper.

2. Foxtrot Mike 9mm Upper Receiver

Foxtrot has a variety of 9mm AR-15 upper receivers, but the most similar to a rifle setup is the 16-inch upper receiver. Converting your AR-15 to a 9mm AR with this length barrel will help you improve your accuracy and allows you to shoot cheaper 9mm ammo rather than 5.56 or .223.

This upper is complete with a non-reciprocating forward charging handle, a BCG with a hard melonite finish, and an M-Lok handguard. Plus FM uses a unique design to connect the upper and handguard which prevents your barrel nut from unscrewing.

This receiver is compatible with any lower that uses Glock magazines, so you can kill two birds with one stone if you tend to run Glock handguns, which a number of my range buddies tend to look for.

3. Angstadt Arms 9mm Upper Receiver

The 6-inch barrel complete 9mm upper is an excellent option if you’re building a home defense or truck gun. This upper is also suppressor-ready, which is a logical addition to this if it is a defensive firearm. The handguard is 5.5 inches long and ultralight. This upper is compatible with any 9mm AR-15 dedicated lower receiver.

This upper includes a 9mm BCG and the high-quality Radian Weapons Raptor ambidextrous charging handle.

4. Stern Defense 9mm Upper Receiver

Stern Defense makes a great mid-length 8.5-inch barrel option, a solid choice for a fun PCC build. This upper is unique as the free float M-Lok handguard extends beyond the barrel’s end, and offers a full-length Picatinny rail up top.

The muzzle includes a blast can to extend beyond the handguard. The Stern Defense upper uses a 9mm bolt that is compatible with Colt SMG and Glock magazines.

5. Faxon Firearms 9mm Upper Receiver

If you’re all about running 9mm carbines in competitive shooting, this complete upper is a great option to match what you’re used to on an AR-15 platform. The 16-inch taper 9mm barrel is accurate for shooting at distance. This upper is compatible with lowers that use both Colt or a Glock mag.

The Gen 2 9mm bolt-carrier group, charging handle, and A-2 style flash hider are all included for a complete drop-in-ready setup.

6. CMMG 9mm Upper Receiver

CMMG is known for high-quality AR- 15 rifles and has broken into the 9mm AR-15 uppers market. This specific model features an 8.5-inch barrel with an M-Lok handguard. The barrel comes with the SV brake muzzle device already installed. This upper is compatible with Glock magazines only and comes with a charging handle and a BCG.

What is an AR9 upper anyway?

Unfinished AR lower and upper forgings
Two main components make up a rifle or pistol caliber carbine, an upper and a lower.

Two main components make up a rifle or pistol caliber carbine, an upper and a lower.

The lower is the only serialized piece that requires an FFL transfer. An upper or upper receiver is the part that contains the BCG and charging handle, and given they’re compatible with lowers you get the same “lego for adults” quality of traditional ARs in the smaller 9mm format.  

The upper is also where the barrel and handguard attach. The most important bit here is the upper and lower need to be compatible and fit together snugly for your firearm to be accurate and safe to fire.

Why a PCC upper receiver?

9mm AR Uppers - Upper and Lower Disassembled
The flexibility of PCCs has driven their popularity over the past 20 years, making them the go-to choice for those who want a multi-role pistol caliber rifle.

Link an AR pistol or SBR but easier

PCC’s came about to fill several needs; 9mm carbines are in the ballpark of AR-15 pistols or short-barreled rifles in terms of interoperable uppers and lowers, but with less hassle around brace rules or federal tax stamps.

You get the benefits of an easy-shooting, reliable upper receiver with less runaround — something I’m always willing to invest in. Curious about the AR barrels? Read our guide!

BCG & Charging Handle
PCC uppers are configured for 9mm ammunition from the BCG to the ejection port and everything in between.

9mm being one of the most popular rounds on planet earth, complete AR9 uppers are chambered in Herr Luger’s cartridge and engineered to integrate with the AR platform. A PCC upper must shoot 9mm ammunition as everything from the ejection port size to the BCG changes to support that specific cartridge. Plus, I tend to find 9mm ammo is considerably cheaper than full-on 5.56 NATO, so you can save a few bucks by transitioning to a PCC for regular shoot days. 

Less recoil but just as much potential

Different 9mm ammo cases brass aluminum nickel
Beyond the ease of use, 9mm round scome in a massive array of options.

PCC’s throw off a lot less recoil than 5.56 and .223 rounds, making them an ideal choice for women or children who want to get familiar with shooting a rifle-length gun without rifle-level recoil.

Mil-spec PCC uppers with a 16-inch barrel are durable upper receivers that can provide the same rifle fundamentals practice with the bonus of saving money using the relatively cheap 9mm ammo.

Lastly, PCC uppers with shorter barrels between 6 and 8.5 inches make excellent self-defense firearms or truck guns. The 9mm is among the most popular defensive cartridges for a good reason, but standard handguns are hard to shoot well: being able to fire 9mm out of an AR platform gives you familiar controls and makes it a lot easier to shoot it well under stress. Plus a suppressed AR9 can be as soft as shooting a .22lr.

Competition Use

Many folks have been using 9mm ARs in competitions to great effect. The longer barrel of most of these uppers, when compared to most standard handguns, gives you a little bit of additional range over a pistol while remaining a small, lightweight package for a quick shooting gun. You aren’t going to get the same range with 9mm as you would from a 5.56mm AR, but if ringing steel plates at about 100 yards is what you expect to do, you might well be able to do it with an AR in 9mm.

A 9mm upper receiver is exactly what you need if you want to get into the world of the 9mm ARs and you already have a lower receiver.

9mm Upper Compatibility

9mm AR Uppers - Upper and Lower Together
The easiest way to build a PCC with with a dedicated 9mm lower & upper. There are mag well adapters for standard AR lowers that make it possible as well.

There are two ways to install a 9mm upper and create a pistol caliber carbine. The easier option is connecting a 9mm upper onto a dedicated 9mm lower. These are easy to install because the lowers are designed to PCC specs, and the mag well is already set up to accept Glock or Colt magazines.

The second way is to attach the 9mm upper onto a standard AR-15 lower with a mag well adapter. AR uppers match AR lowers’ specifications, so the fit with an AR lower and PCC upper may leave a little to be desired.

9mm AR Uppers - Mag Well
A 9mm mag well is a smaller target that a traditional AR mag well, and will require more precision to hit consistently with quick mag swaps.

Essential AR9 Upper Features

  • Purpose. The first question you have to ask yourself is what purpose this gun is serving? Barrel length is the most significant factor when determining your 9mm carbine’s purpose. A shorter barrel will be suitable for defensive situations, and a longer barrel can be used in competition or to replicate the size and weight of a traditional AR-15. Take a look at the muzzle device that comes with the upper receiver. For most purposes, I’m fine with an A2 flash hider. With that said, a more aggressive muzzle brake can help keep the muzzle level, which is key to competitions when every second counts. If you plan on suppressing your 9mm AR once it’s assembled, it’s worth looking around to see if there are options out there that come from the factory with a muzzle device that’s compatible with your suppressor. Otherwise, making sure that the barrel is threaded appropriately for whichever muzzle device you want to add is a must. 
  • Weight. Weight is another factor to take into account. If you struggle to control a fully loaded 16-inch PCC, consider a 10.5-inch. This modularity gives you a great opportunity to get the fit just right, which is a huge benefit for people like myself, who often struggle with one-size-fits-all kinds of products.
  • Optics Support. Also  – any gun is only as good as its sights. It’s rare to find anyone using iron sights on these guns, but those unicorns do exist! Most red dots, for example, will be compatible with Picatinny rails, so ensure your handguard is configured accordingly. 
  • Rail/Handguard System. Similarly, the uppers mentioned above all come with an M-Lok compatible handguard or Lok rail. If mounting a flashlight or laser on the handguard, mount it to the side — and out of the way — of the sights. Mounting systems like M-Lok are so crucial for this reason alone — they keep your sight line clear. If you’re buying this as your first AR, make sure that any accessories that you buy, such as a light or a foregrip of some kind, will work with the rail on the upper, or else you risk having to make some convoluted setup with putting rail sections to convert from one type to another. If you already have accessories, it makes sense to buy an upper that is already compatible.
  • Fit and Finish. The finish is a major consideration here. The AR9 market seems to follow the AR-15 in terms of new finishes, and a lot of folks make their competition guns in fairly bright colors. If that’s something that matters to you, then it’s worth buying an AR9 that you like the appearance of. In terms of performance, a coating that is long-lasting will help extend the life of the gun and prevent corrosion over time: finish is one of the hallmarks of quality ARs and it’s no different whether it’s in 9mm or 5.56mm. 
9mm AR Uppers - Different Handguards
M-Lok & KeyMod PCC uppers. PCC uppers will give you the same rail and mounting options of rifle-caliber uppers, with possibly less overall room given the tend toward shorter barrel length.

Magazine choice matters

Magazine choice is an essential factor in which compete upper receiver you’ll run. Some only use Glock magazines, while others can also accept Colt mags. The magwell for a dedicated 9mm lower can take some getting used to if you’re coming from the traditional AR world — it’s a considerably smaller insertion target. 

Pro tip: if you’re running an AR-15 lower with a magwell conversion, use the inside of the magwell to ease the magazine in. It will take a lot of the guesswork out of reloads and helped me shave a lot of time off my shots.

Drop-in vs building your own

The last consideration is how competent you are in building a 9mm PCC vs. going with an easy drop-in installation. 

While we found the best AR9 complete uppers on the market that require little to no installation, stripped upper receivers allow you to start building a custom PCC from scratch.

Whatever you choose, make sure you know what you’re doing or take your parts to a reputable gunsmith.

Types of 9mm Upper Receivers

Complete Uppers

best ar9 uppers - cover
A complete upper just need to be married to a lower and you're off and running.

Most of the 9mm upper receivers above are complete upper receivers. That means that you’ll be getting the receiver itself, a barrel, and the rail section most of the time, which makes them more expensive than a stripped upper receiver alone, but you get a much more complete package.

Pay close attention to the listings when you’re comparing complete upper receivers: some include BCG, and others do not. At the front of the barrel, there will also be a muzzle device, ranging from a standard A2 style flash hider to more expensive and more aggressive muzzle breaks to soften the already diminutive 9mm recoil even further.

For a more trouble-free AR9 build experience, a complete upper that includes the receiver, barrel, and BCG will simply pin onto any existing AR-15 pistol caliber lower receiver. With the appropriate magazine, it will be good to go . Generally, most fully assembled uppers will also come with a rail section on the handguard upon which you’ll want to place an optic of your choice. I usually go with a red dot on an AR9, as iron sights on such short barrels begin to lose some of their utility.

Stripped Uppers

Second, buying a stripped upper receiver that will include just the receiver body is undoubtedly an option. This is the option to go for if you’re one of those folks who wants the most control when building an AR in 9mm. These will be, generally, cheaper than complete uppers for the simple fact that it’s a single part as opposed to an entire upper assembly.

You’ll also need a barrel, handguard, muzzle device, bolt carrier group, and optic if you go this route. So, if you’re starting from scratch or have some of those parts already, then going for a stripped upper might be the way to go for you.

Whichever option you go with, the fantastic thing about buying an upper by itself is that you can have it shipped directly to your door. Once you get it, all you have to do with a complete upper is pop it on your existing AR-15 lower. Stripped uppers require assembly, but it’s a project that even first-time AR owners can do with success if you’re willing to be patient and take your time.

Pricing of 9mm AR Uppers

  • Under $200. For about $200, it is possible to find even high-quality stripped uppers if a retailer is running a sale. Again, this will be primarily for stripped uppers, and you’d be hard-pressed to find an excellent complete upper receiver for much less than this, though it had occasionally occurred before gun prices went through the roof in the last few years.
  • $300-$400. At around $400, you’ll get many complete uppers that come with a no-frills muzzle device and a nice, if somewhat heavy, rail section. This price range is the sweet spot for the AR9 upper receiver market, and many folks are more than happy with their purchases made at this price point.
  • $500 & Above. Above $500, you’ll be looking at complete uppers that come with skeletonized handguards and some cool muzzle devices. This is where a lot of the more brightly colored options also find themselves, and the more you spend, the higher-quality the fit and finish are likely to be. You can also find a few oddities like side charging uppers as opposed to the standard rear, and the sky is truly the limit in how much you can spend on an AR9 upper receiver.

How we selected these products

As much as I would love to put all these AR9 uppers to the test there are times when certain products or categories are a real challenge — be it availability, cost, or simply a lack of resources — we can get stymied going hands-on with all the potential candidates. Rather than present a never-ending list of all the AR9 uppers on the planet, we selected those which we felt best represent the price points laid out above — giving you a solid representational list to serve as a jumping-off point for your own research (you are going to do you own research, right?)

To avoid disappointment or steering you in the wrong direction, we bolster our own experience with conversations with experts, comb through reviews on retailer sites & sales data, review industry publications, other blogs, and otherwise surface the best information available.

We aim for all thriller, no filler, as they say.


Pistol caliber carbines were purposefully designed for self-defense, competitive shooting, and fun. Whatever your intentions, take your time, pick the upper receiver that will best suit your needs, and most importantly — enjoy your new 9mm build!

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