BROWNELLS BRN-180 SCNR 300 BLACKOUT 9” COMPLETE UPPER RECEIVER ASSEMBLY “The difference is in the details,” goes an old saying. It certainly proves true with the Third Generation of our BRN-180 upper receiver. This redesign incorporates a whole series of detail changes based in large part on feedback received from BRN-180 users, and on our own experience putting myriad thousands of rounds through 180s at our test range. We believe these updates result in a decisive advance in the SCNR’Sergonomics, adaptability, and reliability. Before diehard 180 fans start to worry, we have not changed the BRN-180's long-proven, ultra-dependable short-stroke gas piston operating system based on the AR-180. Or the buffer tube free bolt-carrier assembly contained entirely within the receiver. Or the 180's rugged “of a piece” construction. We kept what was good and right and have improved what could be improved. It is still drop-on compatible with a standard mil-spec AR-15 lower receiver, as well as lowers specifically designed for buffer-tubeless uppers and Picatinny mount stocks. If you own one or more Gen1 or Gen2 models, rest assured that you still have one of the most advanced, innovative, rock-steady dependable AR-15 type upper receivers currently available. If you add a SCNR to your collection, you'll find that it delivers MORE of what the first two “Gens” offered. When you pick up a BRN-180 SCNR upper, the first thing you'll notice when you reach for the charging handle to check the chamber is.... there's no charging handle. Actually, there is, but we've moved it to the left side of the receiver. It is now non-reciprocating, so you don't have to worry about a mass of metal flying back and forth close to your face while you're shooting. The slot it rides in is sealed by a rubber gasket, so the handle moves freely but the interior of the receiver is protected from incursion of dirt, dust and debris. The quirky old “dogleg” charging handle is replaced by a more streamlined, ergonomic handle that angles downward to provide more clearance around your optic's objective bell. When you pull back on that charging handle with the BRN-180 upper separated from the lower receiver, you will NOT get the surprise most of us got the first time we did that with a 180 upper. The guide assembly will not come shooting out the back of the receiver due a new retention system. When it's time to remove the rods and bolt-carrier assembly for cleaning, a quick push of the button lets you remove the assembly - no surprises! Back on the right side, things are even more different. An AR-15 style shell deflector has been added just behind the ejection port. The traditional flip-up ejection port cover has been replaced by a cover that's attached to the carrier. When the bolt-carrier assembly is in battery, the ejection port is sealed. As the carrier moves back, the “automatic” port cover opens to allow the spent shell to depart. Then it seals right back up. All of this means the interior of the SCNR's receiver is superbly protected against incursion of external dust, dirt, or other debris. Up front, we’ve updated the switchable gas system even easier to use. All BRN-180 SCNR now come with a gas block and gas valve coated with a Chromium Tungsten Nitride finish that greatly reduces carbon fouling which makes even easier to use. You reach through an opening in the handguard and flip the lever to one of three gas flow settings. Position 1 for suppressed loads, position 2 for normal operation unsuppressed, position 3 for adverse conditions. If you employ a far forward support hand position, your hand or wrist can be taking some of that gas blast. We've blanked off the surrounding area on the handguard with solid metal to deflect that venting gas. We've just touched the highlights here. Read below for a full rundown of the upgrades we've made to the BRN-180 SCNR! NEW BRN-180® SCNR FEATURES: NONRECIPROCATING LEFT-SIDE CHARGING HANDLE: Gets the charging handle out of the way of the ejection port area and eliminates the flying hunk of metal every time you fire a shot. Left side position enables a better “division of labor” between firing and support hands. Improved Charging Handle Ergonomics: The handle now angles downwards, so it's easy to grasp without having to wrangle your hand around your optic. This also makes manually locking back the bolt much easier. Sealed Receiver Slot: An open charging handle slot would be a magnet for dirt, dust, and debris, so we've sealed it with a special Swiss-inspired rubber gasket that lets the handle move freely but keeps foreign matter out. “Automatic” Ejection Port Cover: We've replaced the AR-15 type cover with a cover attached to the bolt-carrier assembly that cycles with the action and seals the gap behind the carrier when the bolt is forward. You never have to manipulate it yourself. Easy-Adjust Gas System: Simply reach through the opening in the handguard to flip the lever between the Suppressed, Normal, and Adverse gas settings. No tools needed. Lever is easy to disassemble for cleaning, too, with the handguard removed. Stronger Handguard Attachment: The contact surface between the handguard and the barrel, not exactly skimpy before, is longer, resulting in a very rigid handguard attachment with almost no flex, a very stable foundation for aiming devices. Ambi QD Sling Sockets: Added to the top rear of the handguard for more versatility in attaching a sling. The socket cups have a hardened STEEL insert to prevent the swivel from wearing the surrounding aluminum of the handguard. Recoil Guide Rod Retainer: When your upper is pivoted open or removed from the lower receiver, this keeps the guide rod/recoil spring assembly from popping out the back. Simply hit the release button when it's time to remove the recoil assembly. Cleaner Muzzle Device Fitment: A flange added just behind the muzzle threads let you install muzzle devices for .750” O.D. barrels without the special adapters needed on previous 180 generations for a clean transition from the.600” O.D. barrel. Improved Guide Rod Springs: Made of flat wire with more “oomph” to push the bolt-carrier fully forward into battery, even when the gun is heavily fouled and in need of a serious cleaning. Anti-Bounce Bolt-Carrier Upgrade: A protrusion kicks the carrier to the side when going into battery to prevent it from bouncing to the rear. This ensures it's full in battery when the firing pin releases, eliminating the risk of light primer strikes. Steel Cam Path: A full-length steel cam path inside the receiver cuts down on wear from the much harder steel carrier, extending receiver life during extensive shooting, especially with sound suppressors. WHAT MAKES THE SCNR BRN-180 UPPER DIFFERENT? Enhanced Reliability: Upgraded guide rod springs and anti-bounce system on bolt for reliable cycling with heavy carbon fouling. Interior of receiver better sealed from outside dust, dirt, and debris for better dependability in adverse operating environments. Improved Ergonomics: Charging handle more conveniently located on the left side, easier to operate, and safer because it does not reciprocate during the firing cycle. Ultra-Easy, Fast Gas Flow Control: Dirt simple to change gas flow rate with a flip of a lever. No tools needed. Gas system is easy to disassemble for cleaning, making you more likely to do it. Improved Accessory Mounting: This solid accessory mounting platform is now EVEN solider with the extended handguard attachment surface on the barrel nut. Plus, more convenient, versatile sling mounting options with QD sockets at the rear of the handguard. “Sproing!” Surprise Eliminated: Guide rod/recoil spring assembly now has a retention system so it no longer flies out the back of the receiver when the receiver is tilted open on the pivot pin or removed from the lower receiver. Longevity and Durability: Full-length steel cam path vastly reduces wear of aluminum alloy receiver's interior by the much harder steel carrier, greatly extending the receiver's service life. Warning: Do not cycle the action of you BRN-180 SCNR if the upper receiver is not installed on the lower receiver. Doing so could damage the recoil spring guide rod assembly. WARNING!: BE SURE TO READ AND FULLY UNDERSTAND YOUR USER MANUAL BEFORE USE. FAILURE TO DO SO MAY RESULT IN DAMAGE TO THE FIREARM, SUPPRESSOR (IF INSTALLED), AND/OR PERSONAL INJURY INCLUDING DEATH. Brownell’s BRN-180 SCNR Uppers are designed and tested to operate reliably with knowledgeable use and proper care. The use of super-sonic, sub-sonic and standard ammunition loads with or without suppressors will require adjustment of the multi-position gas block system. Failure to adjust the system properly can result in damage to the firearm, suppressor (if installed), and/or personal injury including death. If there are any questions, please contact our Customer Service Department at 1-800-741-0015 available Monday thru Friday 08:00 to 05:00 Central Time. See all of our AR15s and AR15 Parts here.