Recently Brownell’s released their own spin on Eugene Stoner and Arthur Miller’s original AR-18/180 rifle which they called the BRN-180. After widespread desire for a shorter and lighter version, Brownell’s delivered with the newest iteration; the BRN180s. This upper has two options which are a 10.5” barrel chambered in 223 or the 10” barrel chambered in .300 BLK. Each of these seems to be well designed, but for the purposes of the article, I will be writing about the 10.5” chambered in 223 since that is what I have owned and used for about 15 months now.
While the BRN-180S gives the people the shorter platform they desired, it also incorporates two major design improvements over the first-gen uppers. First, they now come with an adjustable gas system. This system only has two positions, on or off. While seemingly simple and intuitive, it caused one of the only two issues I have encountered with this platform. When the gas block was turned to the suppressed setting, I was consistently having cycling problems when using my SilencerCo Hybrid suppressor. I never tried ammo other than 55gr PMC, but when using this ammunition, it just wouldn’t cycle reliably. However, when I flipped the adjustable gas block to the unsuppressed setting and let it stay wide open, I never had another cycling issue. I was originally worried about it being over-gassed, and while it blows the bolt back a little harder than my 11.5” with a finely tuned superlative arms gas block, it has cycled reliably for hundreds of rounds without a hiccup. There also doesn’t seem to be any signs of excessive wear and tear, but I have only put approximately 1000 rounds through it so far (95% suppressed). The only other problems I have had with this platform were cycling issues when using a Magpul B.A.D. Lever. I could never see how the lever was catching the bolt, but as soon as I took the BAD lever back off, the BCG never got locked back again. This taught me the biggest lesson: always test your gear before going out to the field to use it. Sadly, I had thrown the BAD lever on right before going out hunting and ended up getting within 20 yards of 30 pigs to find out in the dark of night that my BCG would lock back after every round. That was definitely a hard lesson, but you live and you learn.
The second main upgrade the BRN-180S incorporates is the use of a single locking screw to retain the handguard. This is designed to provide ample locking force while maintaining a consistent handguard lockup. For those of you who will be running a front sight post or laser, having a rigid rail is key to holding zero. While this is a short and lightweight rail, it remains rigid and held zero for my DBAL D2 about as good as any MLOK rail I have tried. The rail is slim and can heat up quickly if you are burning through mags, but I think the lightweight and low-profile rail goes perfectly with this upper.
The two main benefits I see from the BRN-180S are the short-stroke gas piston and the ability to shoot folded. The gas piston system keeps the upper running clean while keeping fouling out of the receiver. This is also a huge plus for anyone who plans to shoot suppressed. Piston systems mitigate the gas blowback when shooting suppressed, and this platform performs wonderfully. I have shot plenty of short-barreled AR’s, and the gas blowback on suppressed DI systems is just terrible. I have never once had my eyes burning when mag dumping this BRN-180S. Huge thank you to Brownells for keeping the gas piston system the same as ole Eugene Stoner intended.
What really makes the BRN-180S upper unique is its self-contained twin recoil guide rods which create a smooth recoil impulse, all while working without the use of a standard buffer. Being completely interchangeable with standard AR15 lowers, having an upper with a self-contained operating system allows the use of lowers such as the BRN-180 which has a 1913 Picatinny rail section where standard lowers would have the buffer tube threads. This design allows for more flexibility in aftermarket braces and stocks, which can be much more low profile and lightweight than standard folding AR lowers that use a buffer system. The BRN-180S is both unique and sleek for these reasons. Having an AR that can be shot while folded makes for an awesome truck gun. Pair it with a laser and NODs, and you can have quite the night out on the range!
A short video of this platform being shot while folded can be seen on my Instagram page here.
All in all, I have absolutely loved this platform over the last 15 months I have been using it. Once I removed the Magpul BAD lever and opened up the gas block all the way, the BRN-180S has run flawlessly. From a dedicated lightweight hunting gun topped with thermal to a more highspeed suppressed foldy boi, I have not been disappointed. Inspired by the AR-180 of the 1960s, the BRN-180S has taken a modern twist and proven to be reliable, effective, lightweight, and a whole lot of fun.
Below is my complete parts list for my BRN-180S:
Brownells BRN180S upper receiver
Magpul MBUS Pro iron sights
Magpul M-LOK AFG
Silencerco ASR muzzle brake
Brownells BRN180 lower receiver
Geissele SSA-E trigger
Magpul K2+ grip
Sig Sauer 1913 folding mech
JMac Customs AB-8R armbar and AB-BA adapter
Gear Head Works MOD1C Tailhook brace
Isle manufacturing cheek riser
Magpul MS4 sling
The Brownells BRN-180S is a great entry level AR rifle. It’s priced affordably and features a 3-point buttstock, which makes it a good fit for someone looking to shoot in three positions but not willing to shell out the money for an adjustable one. The whole rifle is solid, featuring a durable polymer stock that doesn’t scratch or dent easily – perfect for anyone who likes getting dirty on the range.
Did you use the Sig Sauer 1913 folding knuckle? Cant find anything saying they sell Sig Sauer 1913 folding mech. Thanks
Yea, I am using a Sig 1913 folding mech, jmaccustoms AB-8R armbar and AB-BA adapter, with a gearheadworks MOD1C Tailhook.
Also, good tri-pod aint all that easy to find. I can’t get the suppressor because of the state in which I reside and all the good tri-pods seem to be sold out.