Gun Review: Colt’s CRB-16RR in 300 Blackout

The 300 Blackout is starting to move forward again thanks to the greater availability of ammunition. Unfortunately, its introduction came at height of the AR-buying and ammunition-hoarding craze driven by politics. Of course, there were shortages in supply. While many either wanted to try or even move to this caliber, it was just not possible to get LE-specific ammunition, and market prices were ridiculous. That has started to loosen up a bit, and more people are starting to see the benefits of this caliber. For me, properly loaded, the 300 Blackout remains the best police carbine round available. Supersonic 300 Blackout ammunition offers solid, .30-caliber ballistics out to any practical police range for a carbine. Rifles in this chambering can be shortened and suppressed while maintaining their reliability, providing better ballistics than similarly equipped 5.56mm rifles. Converting existing 5.56mm ARs means simply swapping out the barrel, which can be accomplished at the department armorer level if needed. Existing 5.56mm NATO magazines can also be used, requiring no changes to existing gear.

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Early 300 Blackout development focused on short barrels and subsonic ammunition. Because the cartridge was designed for military applications, this makes sense. Military units wanted a short-barreled and suppressed entry weapon optimized for subsonic ammunition. Built properly, the 300 Blackout system is excellent for this task. Now this arena has expanded to include several 16-inch-barreled carbines and supersonic ammunition with projectiles optimized for self-defense and professional uses.

Colt rifles are some of the most popular among departments, officers and professionals. Most are built to military specifications or are designed for duty use. Several agencies will only allow a Colt for department use. It is easy to forget that the company has been making some of the best competition ARs for years. These rifles have just been hard to get, and they were a very small part of the company’s focus for a time.

But this changed rather significantly when Colt licensed Bold Ideas Texas to build its competition rifles, which are given the Colt Competition name. Built for accuracy, these rifles have been geared towards the competition market, especially 3-Gun. These types of competitions are excellent testing and proving grounds for equipment used for self-defense and duty, so crossovers are pretty common. Not everything makes the transition, but it weeds out equipment and designs that are unreliable. Many top competitors and their rifles will go though more hard use in a season than an officer’s gun will see in its lifetime. Colt Competition rifles are no exception—they are beginning to make the transition to the tactical market, and the direct-impingement Colt Competition CRB-16RR in 300 Blackout is a solid example.

Gun Details

The CRB-16RR starts with a flattop upper receiver forged from 7075-T6 aluminum. Attached to it is a tubular forend with four removable rails that covers a Colt Competition adjustable, carbine-length gas system optimized for accuracy and reliability. No tools are required to adjust the valve in the gas block, and it is easily accessible. Within the handguard is a 16-inch, match-grade, 416 stainless steel HBAR barrel with a 1-in-8-inch twist rate and a SAAMI-spec 300 Blackout chamber. The muzzle has 5/8×24-tpi threading, and a Colt Competition Triple-Port muzzle brake comes equipped. The mil-spec bolt carrier is magnetic-particle (MP) inspected. Finally, the upper receiver features a Colt Competition charging handle with an extended latch.

The CRB-16RR’s lower receiver, also forged from 7075-T6 aluminum, houses a Colt Competition match-grade trigger that is nickel-Teflon coated and breaks crisply at less than 6 pounds. A mil-spec, six-position, carbine-length buffer tube is used, housing a standard H-buffer and spring. Hogue’s rubber grip is mated to a Magpul oversized triggerguard. Magpul’s CTR stock rounds out the rifle. The CRB-16RR is shipped in a box with a nice cleaning kit, one 30-round PMAG, a lock and a test target.

For aiming, I added a Vixen Optics 1-6x24mm Series VIII scope in an American Defense QD single-piece mount, which made it easy to attach and remove the scope with no loss in zero. The scope’s illuminated duplex reticle, positioned in the second focal plane, allows for better aiming at longer ranges.

Mounting a sling was a bit problematic, as there was no way to attach it to the handguard. The tube is solid, with no built-in sling cups. The rails will accommodate several mounts, but none were provided. Since I had several Daniel Defense rail-mounted sling attachments in my shop, I added one for most of the CQB work.

All of the testing was completed with a SureFire M720V light attached. This light allows for either white or infrared lighting and uses a remote switch that can be easily attached to any rail. It can be activated using a momentary or constant-on switch, and it even has the ability to operate as a handheld flashlight with its own activation switch. It is easily one of the most versatile tactical lights on the market.

Range Time

Colt Competition guarantees the rifle will produce a sub-1-inch group at 100 yards using the specified ammunition. My sample CRB-16RR came with a test target showing a group of three Hornady 110-grain V-MAX rounds measuring 0.76 inches. My testing results were close, with my best five-shot group measuring 0.86 inches using the same ammunition. Four of those five rounds were well under half an inch. This rifle was accurate with everything tested, yielding groups at or around an inch. Remington’s 125-grain Open-Tip Match (OTM) ammunition generally rules for 300 Blackout accuracy, but this rifle seemed to favor the 110-grain bullets by just a bit. All of the supersonic ammunition worked well, with no malfunctions.

The rifle’s adjustable gas block is a really nice touch, especially in this chambering. The tendency is to “over-gas” AR-style rifles so they work with most ammunition. Adjustable gas blocks allow you to tune the rifle to your ammunition, however. Patented by Bold Ideas Texas, this gas block is really easy to operate. A large, knurled knob protrudes from the forend. You simply pull it out, adjust it and push it back in. It allowed me to adjust this rifle so that it was very smooth.

Theoretically, this gas block allows you to tune the rifle for subsonic ammunition. While the CRB-16RR ran better with subsonic ammunition than most I’ve tested, it was still not duty reliable with any of this type of ammunition. Adding a suppressor would probably help. It cycled the 220-grain Remington and 208-grain Hornady loads well but would not lock open on the last round. A buffer spring change would likely allow these to function reliably. It would not cycle 240-grain loads.

With any of the 110-grain loads, this rifle was fast, accurate and reliable. It was also very handy, especially at CQB distances. The Vixen scope took some getting used to, but it was pretty fast once I was accustomed to it. The duplex reticle keeps this rig locked into 300 yards and in—maybe 200 yards with this caliber, unless you want to take the time to adjust the knobs. The 110-grain bullets usually drop about 8 inches or so depending on barrel length at 200 yards, making holdovers with no lines possible. That being said, at 100 yards and in, it was fast. With the illuminated reticle for CQB distances, you are basically running a red dot. This scope also comes with a mil-dot reticle, which is probably a better choice for tactical uses.

Moving around the range, the CRB-16RR was well balanced and fast on target. The muzzle brake is also manageable as long as you are outdoors. Taming recoil and muzzle rise nicely, it remains loud. And it’s really loud indoors, as you might expect. If this rifle were to be actually fielded, you’d probably need to replace the muzzle brake with a flash suppressor of some kind. Using full-power ammunition, that is seldom an issue with this caliber, especially with a 16-inch barrel, so any solid flash suppressor will work. Every 300 Blackout rifle I’ve tested has run well with suppressors, so you can also use many of the thread-on suppressors, or those using quick-attach flash suppressors.

Final Notes

As Colt Competition moves into the tactical market, it looks to be a solid choice. This rifle was accurate, well balanced, reliable and pretty well equipped. The trigger was crisp and would fit well within most law enforcement agency policies.

The muzzle brake is problematic for me. I’ve heard all of the arguments, and none of them wash for me. If it is a fighting rifle, it needs to work in a close-quarters environment without taking your fellow officers (or you) out of the fight. Super-fast split times and muzzles that don’t move are way down on the “need” list for a 5.56mm or 300 Blackout rifle meant for duty use. As brakes go, this is an excellent one, and short of a suppressor it would be perfect for a competition, but my preference remains a proven flash suppressor for duty rifles or home defense. On the plus side, the 300 Blackout using full-power ammunition runs great with just about any of them, and the 5/8×24 threading will accommodate most.

It would be nice to see some means to attach a sling. The CTR stock allows for use of QD sling swivels as well as standard attachments. Having rails on the forend allows for lots of choices; I would like to have seen one provided. Slings may not be allowed at 3-Gun competitions, but they are a must for any rifle going into harm’s way—it’s just nice to mount one right out of the box.

All in all, this is an excellent rifle. With just a few changes, it’ll be perfectly suited to tactical missions. It was as accurate as this platform gets short of a precision model. The CRB-16RR’s components and build quality are excellent. If you are looking at the 300 Blackout for a tactical rifle, this would be an excellent choice. Colt Competition as a solid reputation, and this rifle meets that standard nicely.

For more information, visit coltcompetition.com or call 855-308-2658.