The first AR-15 “carbine”: new from Brownells

The three-prong “duckbill” flash hider of the Brownells BRN-605
The three-prong “duckbill” flash hider.

A new and welcome addition to Brownells Retro Rifle series, the BRN-605 in 5.56x45mm (5.56mm NATO) replicates the very first and rare AR-15 “carbine” version that made its appearance in Colt's catalog in 1965. The first Colt's effort at producing a more compact variant, the Model 605 was basically a standard M16 with the barrel shortened by 4.5 in / 114 mm to retain the rifle-length gas tube. This way, the Colt Model 605 barrel was 15 inches (381 mm) long, ending just forward of the front sight base and equipped with a three-prong “duckbill” flash hider. No bayonet mounting lugs were provided, but stock and handguard were the same as standard AR-15 rifles, even if prototypes are known with a shorter 16-inch (410 mm) handguard.

Those early carbines were not a success, to put it mildly: reliability problems plagued them so that they never enjoyed popularity and very few were built. But don't worry: as Brownells claims, they “have eliminated that problem by enlarging the gas port to ensure your BRN-605 carbine runs smoothly”!

Brownells BRN-605 carbine, completing the “nostalgia” series

We already talked about and tested Brownells's Retro Rifles extensively. To sum it up, Brownells already offered a line of complete AR-15 rifles that replicate Eugene Stoner's iconic designs in their original form. These include the BRN-601 model, that recreates the classic design of the original Model 601 issued to the US Air Force in the early 1960s, the XBRN16E1 model that replicates the design of the first AR-15 to be issued in mass numbers to US Army on the ground in Vietnam, and the BRN-16A1 Rifle, that replicates the classic M16A1 rifle. They also manufacture a XBRN177E2 version (a replica of the rare Colt CAR-15 Commando assault carbine) and the very early AR-10 models. 

The first AR-15 “carbine”: new from Brownells
The lower has the partial "fence" around the magazine release, while the upper has a forward assist but no shell deflector

The BRN-605 is a nice completion to this extensive lineup of “nostalgia” rifles. It is built around Brownells XBRN16E1 upper and lower receivers (replicas of the XM16E1 parts). The lower has the partial "fence" around the magazine release, while the upper has a forward assist but no shell deflector. Actually, very few original Colt 605s – if any – had a forward assist since they mostly featured a “slickside” upper or a Colt model 603 upper which had the forward assist machined off. Moreover, the barrel of the replica is 15.5 in long (originals were 15 in) But these are just venial sins. Like the original, the entire bolt / carrier group is chrome plated. The magazine has a capacity of 20 rounds.

MRSP for this nice, affordable replica of a very rare early “stubby” AR-15 is 1299.99 USD (price may vary in your country due to VAT and taxes). The BRN-605 is currently available in the US for pre-order.

Brownells BRN-605: technical data




5.56 mm NATO

Barrel length:
15.5 in
Overall Length:
34 in
Magazine capacity:
20 rounds
Price (MRSP):
1299.99 USD

We tested the Brownells Retro Line rifles: read more and watch the video here on