Cry Havoc: Tactical Quick-Release Barrel Kit for the AR-15 Family of Rifles

“Cry ‘Havoc’, and let slip the dogs of war.” This is a familiar saying to those who had to memorize Shakespeare’s “Julius Caesar” back in school. However, the phrase actually first saw the light of day when it was published in the Black Book of the Admiralty in 1385. It had to do with a call for revenge using everything at the navy’s disposal.

These days, a company located in Palm Bay, Florida, has appropriated the saying as their company name. And … considering their products, they might not be far out of line. Cry Havoc Tactical (CHT) is marketing a quick-release barrel kit for the AR-15-type rifle (QRB Kit). The idea behind the barrel release kit is to have an AR-15 rifle, or carbine, that is small enough to fit into a backpack. If you have a barrel at least 16 inches in length, about the shortest rifle you could own would be slightly over 26 inches in length, counting the receiver group and the barrel. Disassembling the rifle by pulling the two push pins still leaves you with an upper receiver/buttstock too long to fit comfortably into a standard backpack.

The Quick-Release Barrel Kit from Cry Havoc Tactical consists of five pieces and can be mounted on a rifle with no changes to the rifle.

Cry Havoc Tactical took a hard look at some AR-15 short rifle conversions; however, most of them didn’t hold zero when broken down and reassembled or were unnecessarily complicated. CHT decided that rather than separating the rifle by using the push pins, they would design a barrel release kit that separates the barrel from the upper receiver. That way, the overall package could easily fit in a laptop case or briefcase without having to go the route of building and papering a short barrel rifle (SBR). An SBR by definition is a rifle that has a barrel less than 16 inches in length, or less than 26 inches in overall length. These are controlled under the National Firearms Act (NFA) and require approval from the BATFE. Until you get the BATFE approval letter, you cannot have possession of the parts needed to build an SBR. The ATF considers having all the parts in your possession just the same as having the fully assembled rifle. They have no sense of humor when it comes to ATF violations, and if you are caught with what they term “constructive possession,” you will get a very close-up and personal introduction to federal law enforcement. Military and LE users do not have this worry, although in the US, these still require registration and transfer. If it is a machine gun, then any barrel length will be fine, the machine gun registration will allow for that.

So, what CHT did was design a kit that allows an AR-15 owner to build a take-down rifle that still classifies as a Type One firearm and is completely legal. An SBR upper/barrel assembly can have an overall length of 21+ inches when built with an 11-1/2-inch barrel. The QRB longest piece is 17.5-inches. This is with a 14-inch barrel with a 1-1/2-inch flash hider permanently attached.

The main clamping levers hold the barrel to the upper receiver. The gas tube is altered so it can be removed.

The QRB kit consists of a hard-anodized aluminum main body, stainless steel hooks, levers, star nut and gas extension tube. If you are capable of installing a barrel on an upper receiver, you can install this kit. However, CHT recommends that either a gunsmith do the conversion, or that your rifle is sent back to CHT where their experienced technicians will do a professional installation. The modification does not require any changes to your AR-15. It can be converted back to stock configuration in the same amount of time it takes to install the kit.

Once installed, the QRB kit is simple to operate. Remove the magazine, lock the bolt back, insert the barrel into the adaptor, line up the gas tube and locating pin and then seat the barrel and close the locking levers. Removal is almost the reverse. Because of the tight barrel-to-adaptor tolerance, the locking levers may have to be extended out slightly to move the barrel out about 1/8 inch. Then the barrel can be removed by hand.

The receiver is on the right. The barrel slides into the adapter, and the clamps hold it all together.

Shooting 5.56 /300 Blackout

For research purposes, I fired a carbine based on a Kaiser with their KSP X-7 polymer upper and lower receivers. CHT had fitted it out with their QRB kit, but went a ways further and provided two different barrels in two different calibers. Both the 5.56 x45mm and the .300 Whisper/Blackout can use the same mag and bolt so other than changing the barrels, no other modifications were required. The first was a Bravo Company 5.56 BCM-KMR-A9 KMOD rail holding a 9-inch barrel. The second was an Advance Manufacturing Tactical CQB 9.7-inch suppressed barrel in .300 Blackout. Both calibers feed from a Magpul PMAG20 5.56 magazine. Both barrels qualify as SBRs, so BATFE paperwork and tax stamps had to be acquired for each caliber. Each barrel assembly had Troy iron sights mounted, and in addition, the 5.56 barrel had a Primary Arms MD-ADS Advanced Micro Dot red sight. As an aside, the CR 2032 battery in the red dot is said to be good for 50,000 hours. The upper receiver also had Troy iron sights.

Due to the iron sights, shooting range was held to 50 yards. Three different loads were fired, all Black Hills Ammunition:

1. 5.56mm 77 grain OTM–2,750 fps, 1,293 ft/lb energy
2..300 Blackout 125 grain OTM–2,220 fps, 1343 ft/lb energy
3..300 Blackout 220 grain OTM–1,000 fps (subsonic), 488 ft/lb energy

The barrels were changed frequently and only allowed to cool enough to remove by hand. The 5.56 out of the short, un-suppressed barrel was quite loud, with a fairly large muzzle flash. Both .300 Whisper loads were quite comfortable to shoot, and the sound, while not totally diminished, was reduced to manageable levels. The subsonic 220-grain loads didn’t have the supersonic crack of the other two calibers and were relatively tame to shoot. The suppressed 220-grain loads were not fired over a sound mike, but general opinion was that they sounded like a .38 Special. More than one person said the short-barreled 5.56mm was unpleasant when fired within 15-20 yards.

The star ring interlocks with the clamp on the barrel. The two small upper holes are for the locating pin and the gas tube below.

The QRB kit had no malfunctions and was checked for return to zero when changing barrels, or just pulling one off and remounting it. The fit stayed tight throughout all the range work, and there was no discernable change in point of impact at the short ranges we used. The .300 Blackout 220-grain load was run through a magazine dump at 25 yards, and while it didn’t shoot MOA, it sure shot MOBG (Minute of Bad Guy). It was easy to hold on target, and recoil was so controllable that reacquiring the target after a shot was quickly and easily accomplished. One 20-round dump was done without taking the rifle off the shooter’s shoulder, and all holes in the target could be covered with one hand.


Cry Havoc Tactical, Inc.
P: 321-537-2141
QRB Kit: $349.00
Factory installation–Contact the factory

Advance Manufacturing builds the suppressed barrel in .300 Blackout.
20 rounds, 25 yards, rapid fire. Lots of firepower in a little package.
From the left: .300 Blackout–125 grain; .300 Blackout–220 grain; 5.56 mm–77 grain.