Brownell's BRN-180S (.300 BLK) Semi-Auto Pistol with Geissele SSA-E Trigger and 1913 Folding Knuckle Brace Bar with Tailhook Mod 1C

1 in stock


This BRN-180S was assembled using an F-1 Firearms FDR-15 Lower Receiver and a Brownell’s BRN-180S (Gen 2) Complete Upper Receiver and numerous uptrade parts.

The BRN-180S (Gen2) is now available in a 300 Blackout Configuration!  Designed in conjunction with any mil-spec lower receiver, the Brownells BRN-180S Complete Upper Receiver is the newest iteration of the BRN-180.  The BRN-180S shares a large chunk of components with the BRN-180, but introduces key features to improve reliability and usability in a short configuration.  The 300 Blackout caliber required a shorter system to ensure reliability with a wide variety of supersonic and subsonic ammunition. This resulting shorter system also required a cutout in the handguard to access the two-position adjustment.  The user can select between these two settings to find the most reliable configuration with their ammo and suppressor.

The BRN-180 Gen2 Upper Receiver Group improves upon the original BRN-180 with two main upgrades;  First, all BRN-180 Upper Receivers now ship with an Adjustable Gas System, previously only found on the BRN-180S.  The operating mechanism, the short stroke gas piston concept remains the same, but the user can select between two settings, depending on their conditions and ammunition, to ensure smooth and consistent function.  No more spare gas piston cup to worry about.

In addition to the new Adjustable Gas System, the Handguard is now retaining with a single locking screw.  This large screw provides ample locking force and ensures a more consistent handguard lockup than the previous mechanism. During extended firing, and the barrel heating up, this new locking system ensures the handguard retains alignment and rigidity with the upper receiver.  Also, with this new takedown mechanism, the handguard can be removed to access the gas system without removing the internal components.

Like the original AR-180, the BRN-180 bolt carrier rides smoothly on a PAIR of guide rods.  The carrier is buffered at the rear by a built-in polymer buffer with a molded-in steel plate that captures the guide rods. The Nitride bolt replicates the original AR-180 bolt design, right down to its use of a standard AR-15 extractor. The barrel is machined from extra-strong 4150 carbon steel, with a hard Nitride finish that really resists surface wear.

The 300 Blackout BRN-180 also features a 1-8 twist for a wide variety of ammo usage.  Up front there’s a replica of the AR-180’s unusual three-prong flash hider: the hemispherical bottom prong helps prevent the muzzle blast from kicking up a dust signature when shooting prone.   Standard 5/8-24 tpi muzzle threads let you swap on a modern AR-15 muzzle device should you be bitten by the customizing bug.


This particular BRN-180S pistol comes with the following upgraded parts:

  • F-1 Firearms FDE-15 Lower Receiver
  • Machined 7075 T6 aluminum receiver & handguard – hardcoat anodized finish
  • 10” barrel with matte black Nitride finish
  • 300 AAC Blackout chamber
  • Button rifled bore; 1-8″” twist 300 Blackout
  • Replica 3-prong AR-180™ flash suppressor
  • Molded polymer ejection port cover
  • CZ Custom Folding 1913 Knuckle Bar with Tailhook Mod 1C
  • Geissele SSA-E Two-Staged Curved Trigger (2.90 lbs)
  • One Lancer L5AWM 300-BLK Magazine
  • Magpul MOD K2 Grip
SKU: 078-000-609 Categories: ,


Additional Information
TypeAR Style Pistol
Caliber.300 BLK
ActionSemi-Auto (Gas Operated)
TriggerGeissele SSA-E Two Stage Curved Trigger (2.9 lbs)
GripMagpul MOE K2 Grip
Barrel Length10″ (1:8 twist)
Overall Length28″ Extended;  20″ Folded
Weight5 lbs 15 oz
Pistol BraceCZ Custom Folding Brace Bar with Tailhook Mod 1C
MagazineOne Lancer L5AWM 30-Round .300BLK Magazine
Product UPCBRN-180S-CZC

Additional Information Content

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