2020 Editor’s Choice Award – Rock River Arms RUK-9BT 4.5-inch

Rock River Arms RUK-9BT 4.5-inch


A packable, home/vehicle/close-quarters defense specialist

 Pistol-caliber ARs are fast, accurate, reliable and fun, making them hard to put down. In short, they are huge smile makers. Hand one to most anyone, fan or otherwise, and a grin slowly shows its presence after the first magazine. The trick is in choosing a good one, and Rock River Arms has introduced an excellent out of the box 9mm AR pistol in the RUK-9BT.

The BT-9G starts with a machined billet-aluminum lower using a Glock compatible flared magwell and integrated oversized trigger guard. SB Tactical’s SBA3 stabilizing brace allows it to be classified as a pistol. Hogue’s rubber grip provides comfortable control. The trigger is the excellent RRA 2-stage model, and the thumb safety is the equally excellent RRA Star Safety Selector. The extruded aluminum A4 upper houses a 4.5-inch chrome-lined chrome moly vanadium barrel with a full-auto chamber and 1:10” twist rate. Threaded 1/2 x 36 tpi, the muzzle is capped with a Smith Vortex flash hider. The handguard is light weight, free floating, M-Lok compatible and 4.25 inches long. It includes RRA NSP flip up sights, low-profile handstop and one ETS clear polymer Glock 17/19 compatible magazine. Leupold’s LCO red-dot sight was added for testing.

Between the upper receiver’s rail and that of the 4.25-inch M-LOK handguard, there was just barely enough Picatinny real estate to run the included flip-up sights, a Leupold LCO RDS and a SureFire X300 Ultra weaponlight. Barrel is 4.5-inches long, chrome-lined and topped with a Smith Vortex flash suppressor. Handstop is included.

Even with the stubby 4.5-inch barrel, accuracy of the BT-9G was impressive. At 25-yards it all but stacks high-quality self-defense ammunition. My best efforts came with the Federal HST 124-gr. +P, with the Wilson Combat 115-gr. Bill Wilson Match in a very close second place. The Bill Wilson load was so soft shooting it was almost frightening, and I had to check a couple of times to make sure it actually went off. Even with the lower velocity, it kicked empty cases out into a nice little pile and the bolt locked open on the last round. I noticed the increased recoil with the +P ammunition, but it still remained comfortable during rapid fire strings.

25-yard precision was outstanding with Federal’s HST 124-gr. +P load. Soft shooting and precise, our test gun ran with 100% reliability with all loads and with the various Glock magazines on hand.

These compact weapon systems excel while working in and around vehicles and moving through tight spaces. Muzzle blast is certainly noticeable with a 9mm, but nothing like a rifle cartridge fired from a similar length barrel. Recoil was also minimal, making it easy to stay on target during rapid fire at CQB distances. Moving among pallets and other obstacles, the short barrel facilitated maintaining cover.

The oversized magazine release is also in just the right spot for quick, fumble-free manipulation. The hand stop was helpful, and the Smith Vortex flash hider allowed me to hook my finger in front, but—for reasons that should be obvious—you need to be ultra-careful about doing do. The hand guard is excellent, but definitely on the short side for my large hands. You can add M-Lok attachments, but they will eat up grip space quickly.

The RUK-9BT ships with one translucent ETS clear polymer magazine, but is compatible with any 9mm Glock magazine — including the factory-Glock 33-rounder shown. You’ll never fumble for the large, serrated mag release during speed reloads.

With a lens providing an excellent, obstruction-free field of view, Leupold’s LCO is one of the best red-dot sights on the market today, and one that often gets overlooked. The 1-MOA dot is clear and crisp (even with my astigmatism) and adjustments can be made in the field with an expended case—no proprietary tools needed. With a very rugged housing, and waterproof to 66 feet, it’s designed to take a beating. Rock River’s supplied flip up BUIS co-witnessed in the center of this optic.

The bottom line is that every time I test one of these pistol-caliber ARs it’s difficult to send it back at the end, and this was particularly true with the very-well equipped, reliable and very accurate Rock River BT9G, and if you are running a 9mm double-stack Glock you will have plenty of compatible magazines. See it at your gun shop, or contact Rock River Arms; Tel.: (866) 980-7625; Web: www.rockriverarms.com—Dave Bahde

At the rear is SB Tactical’s SBA3 adjustable pistol brace and tacky rubber-overmolded RRA handgrip. The trigger is the RRA two-stage, surrounded by an integral, enlarged trigger guard, and the safety selector is the RRA Star model. The RUK-9BT would be a very handy package within in the confines of a vehicle, a small room or any close-quarters situation you might find yourself in.