[Video+Review] BRN-180 Gen 2 Upper: History Dorks Rejoice

True innovation rarely comes to the firearms market, but when it does, it happens with a bang.

The AR-180, while a commercial failure itself, was fundamental to the modern evolution of firearms worldwide — but it never got the credit that it truly deserved.

While the AR-180 deserves an article all its own, we’re looking at the Brownells BRN-180 today! An upper designed to be as close to the original as possible while also working with the AR-15 lower.

From history to functionality, we’re going to break the BRN-180 down and see just how good it really is.

If you’re interested in learning more about the BRN-180 and especially the Gen 2 upper, John has the deets in the video below!

If you like that kind of content, be sure to subscribe to the Pew Pew Tactical YouTube Channel!

History Class

So, I’m a total AR-180 dork.

I thought it was one of the coolest rifles ever designed long before Brownells announced their efforts to bring it back in a modern way.

For me, this is wicked cool right off the bat. If you’re not interested in the history, it’s okay to scroll down. But you’re missing out!

I’m also a firearms guy. If there’s a gun, I want to shoot it and learn the history behind it.

But what I like most are firearms that were almost famous. 

For every firearm on the market, there are dozens that didn’t make the cut. I’m fascinated by these lost models that were too ahead of their time, too expensive to produce, or simply failed to find the right market.

In most cases, these firearms are mechanically sound; they just couldn’t shine in a market saturated with slightly better or cheaper options.

One of my favorite examples is the ArmaLite AR-18/AR-180.

ArmaLite is the legendary company behind the AR-15 (but you know that). Oddly enough, our story begins with ArmaLite selling the rights for the M16 to Colt.

With better connections and more manufacturing capability, Colt was able to sell the rifle to the US Army.

That kind of left ArmaLite out in the cold; their awesome design had been adopted, but they couldn’t make any more money off of it.

So, they came up with Plan B: the AR-18.

Designed by the same team that created the AR-10/AR-15, the AR-18 was designed to resolve some of the weak points of the AR-15 while also making the rifle cheaper and faster to produce.

ArmaLite needed to stay clear of the patents and designs they had just sold to Colt, so that meant building a very different rifle.

The result was a short-stroke gas piston, rotating bolt, steel sheet metal stamped receiver, side charging, stock folding, buffer tube-less, 5.56x45mm NATO rifle. 

What Happened Next?

Nothing. Throughout the next couple of decades, ArmaLite manufactured about 24,000 AR-180 rifles (the semi-auto version of the AR-18), but the weapon failed to gain any traction in the US or overseas.

The Army followed through with their adoption of the M16, and no other nation or major police force adopted the AR-18 or AR-180.

This design was the AR-10 all over again. It was just a little too cutting edge, and it had issues in early adoption testing.

The manufacturing process of stamped steel and welding was revolutionary at the time.

Although it cut down production costs and increased manufacturing speed, the process wasn’t fully trusted by the powers that be.

Keep in mind that this was before the M16 would take the world by storm — asking people to go from forged steel and walnut to aluminum and plastic was a big step.

Asking them to go from forged steel and walnut to stamped steel and plastic was just a step too far.

There is so much to tell about the AR-18, but most of it is history geek stuff.

From production companies to licensing rights to the IRA’s use of stolen AR-18s during The Troubles, the AR-18 is a great rifle to read about.

But what makes it so important to firearms development?

While the AR-18 was too new for its time, it didn’t take long before a whole new generation of firearms, inspired heavily by its design, would spring up in its wake.

The Legacy Of The AR-18

Once the AR-15/M16/M16A2 and AKM/AK-74 softened the ground and showed the world that a high velocity, intermediate cartridge fired from a select-fire lightweight rifle was highly combat effective — everyone wanted one.

How many firearms wouldn’t exist in their current forms if not for the AR-18? If such a list existed, it would probably include almost every modern Western combat rifle.   

The British SA80, American Remington ACR, Belgian FN F2000 and SCAR-H/L, Japanese Howa Type 89, German H&K G36 and 416 – these firearms owe many of their design elements to the AR-18.

Of course, this also applies to any derivative variants, including the American USMC M27 IAR, French 416F, British L85A2, New Zealand MARS-L…the list just goes on.

The AR-18 was never adopted and officially became a commercial flop at 24,000 units. But the rifles that stemmed from the AR-18 number in the millions.

Without the AR-18, the standard-issue rifles of France, Germany, the United Kingdom, Japan, South Korea, the United States Marine Corps, and dozens of police and federal agencies might look a lot different.

So, how does the Brownells BRN-180 stack up? Let’s find out.

What Is The BRN-180?

Brownells set out with a simple goal: Bring the AR-180 to the modern market with as little redesign as possible while also making it functional with the AR-15 platform.

As always, the devil is in the details, and the actual engineering that went into this project is worth major kudos.  

In the end, I believe that Brownells accomplished their goal 100%.

Using the same short-stroke gas piston system, reciprocating charging handle, quick detach handguard, and captured BCG/buffer-less design, the BRN-180 hits all of the high notes.

My BRN-180

Sadly, due to the legal restrictions in California, I couldn’t just throw the BRN-180 on a lower at hit the range. Instead, I needed to make it “featureless” first.

The flash hider was replaced with an Ultradyne C4 Dynamount Folding Sight with Apollo S Muzzle Brake.

For the funsies of it, I picked up an NDS-1815 lower. Why not, right? It’s based on the OG AR-18 lower and takes standard AR-15 parts.

Ironically, I bought it the day before Brownells announced their BRN-180 stripped lower.

But this is the rare case where Yhprum’s Law beats Murphy’s Law. I actually prefer the NDS-1815 lower because it takes a standard buffer tube. For me, this model just works a little better.

A fin grip, stock stop, and optic later, and my BRN-180 was ready to hit the range.

Range Report

As cool as the history and design are, none of that matters if the gun doesn’t run.

After close to 2,000 rounds of .223 Rem and 5.56 NATO through my Gen 1, I can confirm that this gun runs.

Zero failures of any kind, zero cleanings of any kind, just shooting, shooting, and more shooting.

Right off the bat, I’m impressed with the fit and finish. While I’ve never gotten to play with a mint condition AR-180, it feels like this is close to what it would be like.

Manual Of Arms

Since this isn’t a normal AR-15 upper, there are a few differences in how to operate it. The charging handle is probably the greatest example.

Employing a reciprocating charging handle on the right side, it kind of feels a little AK-ish when you use it.

But due to the major dog leg design, it stays completely out of the way while also acting as its own brass deflector.

The weird part, for me, was how little you actually end up using it. After shooting AKs for so long, my brain kind of wanted to treat it like one and use the charging handle on each mag change.

But since this sits on a normal AR-15 lower, the bolt-hold open is fully functional and never failed me.

From steel Wolf ammo to Hornady Black .223, the bolt always locked back on an empty mag.

Accuracy

Back in the day, ArmaLite offered a 2.75x20mm scope for the AR-180. Wanting to stay true to that idea, I paired my BRN-180 with an SWFA 1-4x24mm LPVO.

Shooting tight groups at 100 yards with a 4x scope is definitely not conducive to getting the smallest groups possible.

Due to this handicap, I wasn’t expecting outstanding results.

A standard AR-15 is generally 2.0-2.5 MOA, a really nice AR-15 is closer to 1 MOA, the BRN-180 was mostly standard around the 1.3-1.5 MOA range, but sub-MOA wasn’t totally uncommon either.

I was amazed that the Aguila ammo shot that well. Not bad for 28 cents a round…pre-2020.

My standard range ammo, Wolf Gold 55gr, did very well at 1.35 average MOA.

The Wolf Steel cased ammo I tried was the worst at 2.57 MOA.

I quickly discovered that this rifle likes ammo heavier than 55 gr.

Chambered in .223 Wylde with a 1:8 twist rate, the 55gr ammo was properly stabilized — but universally shot larger groups than 62gr options.

The furthest I pushed my BRN-180 was 250 yards, but going 10 for 10 on a 10″ plate was no problem.

BRN-180 Parts and Internals

If you want to learn about the AR-180, I strongly recommend the Forgotten Weapons and Small Arms Solutions videos on the rifle, as both are outstanding resources.

By understanding the basics of the AR-180, you can fully appreciate the engineering that went into the BRN-180.

All of the basics of the AR-180 are carried over into the BRN-180: the bolt, gas system, field stripping, and design are all the same.

But for all their similarities, the modernized BRN-180 is still better in almost every way.

The actual bolt of the AR-180 was not a design that ended up in Colt’s hands, so it is very close to the AR-15 bolt.

One of the defining features of the AR-180 are the dual guide rods and springs that make up the buffer assembly. This is the heart and soul of the system that permits it to fire without the use a buffer tube.

It also allows for the upper to be field stripped into a surprisingly few number of parts.

Pro tip: When you first strip it, don’t point it so that the rear of the upper is pointed straight up. You might send a guide spring flying and spend a half-hour searching for it…don’t ask how I know.

I bought my BRN-180 upper about a year ago and have the Gen 1 version. They’ve changed the mounting system for the Gen 2 version.

Keep that detail in mind for a moment.

The BRN-180 features a very modernized handguard with an M-LOK rail, but the Gen 1 version of the design and attachment is the same as the AR-180.

To remove the handguard, you first need to field strip the rifle and remove the guide rods and BCG. After that, all you need to do is remove a retaining clip from around the front trunnion to release the handguard.

The clip was VERY stiff when I first got my upper, but it does have a small hole in it, so you can use a cartridge tip to pry it open.

After some use and taking it down a few times, the clip has eased up a touch, and I can now do it by hand.

The Gen 2 features a simple nut in place of the clip. The history geek in me hates this decision, but it does work nicely.

Suppressors

Living in California, I don’t have the freedom to get cool toys like suppressors. But that doesn’t stop the BRN-180 from being able to accept them!

For the Gen 1, I have two piston cups — one for normal shooting, one for suppressed. I couldn’t test the suppressed setting cup, but I’ve heard reports that it works.

The Gen 2 system is improved with an adjustable gas block instead of different piston cups. This is a much better design that’s easier to use, so it’s nice to see.  

Extras

Ultradyne C4 Dynamount And Apollo S

Due to the law, I needed a brake for my upper.

Due to being a dork, I wanted cool iron sights to make the BRN-180 a little closer to the design of the AR-18.

Ultradyne offers an awesome folding iron sights and muzzle device set up that is totally different from the rest of the market. This innovation is perfect for a rifle that was bleeding edge back in the day.

Apollo S Muzzle Brake

This brake is t h i c c. Sitting 5 baffle chambers long, it’s freaking massive. There is no question that for 5.56, it’s overkill. But it’s the good kind of overkill.

The BRN-180 doesn’t have any notable recoil over a standard AR-15. If anything, the impulse is a little different, but that’s it. Using a super beefy brake/comp makes it silly easy to control.

In fact, the rifle muzzle rise is so well combated by the Apollo that it has a very slight negative muzzle rise, meaning that the muzzle tends to go down slightly on every shot.

It’s also a complete lane clearer. While this isn’t the most aggressive side blast brake I’ve used, it is close.

At the end of the day, it’s an awesome device. It’s overkill for 5.56, but in the best way possible.

C4 Dynamount Iron Sights

I’ll be the first to admit that I’m not really an iron sights guy.

Even though I learned to shoot with irons, I didn’t really go gun crazy until decent red dots were wildly available.

These days, I never really force myself to use irons unless I absolutely have to.

Most of my time behind irons are with milsurp rifles.

That said, I’ve shot with standard AR-15 irons and a large range of BUIS, and the C4 Dynamount is by far my favorite.

Both the front and rear sights are folding with the rear sight mounted on a Picatinny rail, and the front sight mounted directly to the barrel.

You might have to fuss around with the Dynamount front sight, which is sandwiched between a locking ring and the muzzle device, to get it correctly timed on the barrel.

But it’s totally worth the time and effort, as it increases your sight radius and delivers the best potential accuracy possible.

Toolless elevation, windage adjustable, super durable, and with an amazing sight picture — there is a lot to love about these irons.

SWFA 1-4x24mm Scope

Right out of the box, the glass quality and turrets on this scope are absolutely outstanding. For the price, this punches way outside of its weight glass. I love that in a scope.

The reticle is…different. After 2,000 rounds, I can’t say I love it, but it’s not bad either. Just not perfectly to my taste, I think.

With a center diamond and outer mil hash marks, the reticle is simple. The diamond is easy to pick up, but the inner dot is almost invisible at all magnification levels.

According to SWFA, the reticle should be zeroed so that the top of the diamond is 100 yards, the center dot is 200 yards, and the bottom point is 300 yards.

It worked, but I didn’t like the feel of it, so I re-zeroed and made the center of the diamond 100 yards instead.

After that, shooting was much more intuitive for me.

While this scope does come with illumination, it’s rather dim. If you’re in low-light, then it is bright enough, but it is almost imperceivable in the daylight conditions I tried.

Something that we’re seeing on a lot more scopes these days is integrated throw arms on the magnification adjustment ring.

I’m all for it – these are almost always a huge improvement and allow for the ring to be stiffer without slowing you down when you need it.

The upside is that the SWFA 1-4x comes with one! But the downside is that it broke off on the way home from my first range trip with it. Snapped off right in the bag.

I’m not sure how it happened, since the bag wasn’t dropped or thrown around. This was a pretty solid disappointment for me.

Overall though, I really like this scope. It’s very durable, the turrets are outstanding, and the glass is absolutely the best of any LVOP I’ve tried under the $1,000 mark.

By The Numbers

Reliability: 5/5

Close to 2,000 rounds is a solid amount of lead to see how a gun performs, and the BRN-180 ran flawlessly. I am entirely impressed with it.

Ergonomics: 5/5

It’s an AR-15, so the ergonomics are great. It feels a little odd at first, but that quickly fades to the background.

Accuracy: 4/5

While my upper and my ammo work amazingly well, Eric’s Gen 2 upper and most other BRN-180s I’ve seen online shoot more like 2-2.5 MOA.

Customization: 3/5

The upper itself isn’t hugely customizable. There are no other barrel options, there are no other handguard options, and there are no other charging handle options.

Optics and a muzzle device are about all you get.

Of course, you can buy the whole upper in 300 BLK now, so that’s cool!

Value: 4/5

This isn’t a cheap upper, but there is a LOT of engineering that went into it. If you’re a history dork, this is a clear winner. But if you want this to be a plinker, you might be a little short.

It can serve in a tactical or home defense role, though. While I got the 18″ barrel, it does come in 16″ and 10.5″ options.

The 10.5″ on a pistol lower would make for an incredible truck gun, pack gun, or home defense firearm.

Overall: 5/5

Conclusion

The BRN-180 Gen 2 Upper brings all the history of the AR-180 and modernizes it. Utterly reliable and fun to shoot, however, you might have some troubles upgrading it besides optics and muzzle device. Accuracy also varies between excellent to standard AR-15. As a history dork, I love this upper. As a firearms guy, it’s a very solid upper.

If I had to choose a single upper, I would probably go with a normal AR-15 upper because of the wide range of parts available on the market. But if I were allowed two choices, the BRN-180 would be high on my list.

It’s such a fun upper.

Someday I’ll turn this rifle into a completely modernized AR-180 build, but until then, this is a rifle I enjoy taking out to the range and rolling into the occasional 2 gun match with.

At SHOT 2020, Brownells told me that they are coming out with a side folding buttstock that matches the old AR-180 look, so I’m really looking forward to that also!

What is your take on the AR-180 and the BRN-180? Will you get one to keep modern or to build as a retro? What other retro guns do you want to see from Brownells? Let us know in the comments! For another awesome retro offering, take a look at the Brownells BRN-10!