What is a 8.6 Creedmoor?
First off, it is now officially called the 8.6 BLK or 8.6 Blackout, dubbed such by the very creator Kevin Brittingham. Kevin, owner of Q and inventor of the .300 Blackout cartridge first came up the with idea of a .338 caliber cartridge like the .338 Federal, but better because it has a shorter 6.5 Creedmoor based case, so it could accommodate larger and longer bullets than the .338 Federal in normal magazines, which would mean it could provide for a cartridge that could be effective at both subsonic and supersonic muzzle velocities. Not only does this owe for interesting low-noise subsonic rifles, but also for short barrel, high-punch rifles and even a cartridge being able to feed in a semi-auto configuration.
Back in 2018 when Kevin initially developed the cartridge and worked with the idea, trying to get Hornady to start manufacturing the cartridge, he intended to call it the 8.6 Creedmoor, but in June 2021 when Q made the official announcement of the cartridge on their Instagram account, they dubbed it the more appropriate 8.6 BLK or 8.6 Blackout, owing to their own unique .300 Blackout, but necked up to accommodate the 8.6 caliber bullet, and also uniquely identifying it as separate from the Creedmoor sports developed cartridges like the 6.5mm Creedmoor and the 6mm Creedmoor.
The reason why Q and Hornady are only now officially bringing it to market in 2021, is mainly because of the ammo crisis that hit since early 2019, which meant that they could not even keep up with demand of current cartridge ammo, let alone start manufacturing or marketing a new cartridge.
Brass
Why a New Cartridge
Yes, it feels like every week someone is just necking some other cartridge up or down and “bringing out a whole new cartridge”, but this time, it is really a game-changer. The 8.6 BLK is not just an improvement on previous designs or a wildcat, it changes what was thought best for hunting cartridges and tactical military cartridges all together. It shows that large long bullets can work out of small cases, and even better, high energy effective hunt kills can be made out of short barrels, even at what would be considered long range distances for hunting.
Create Your Own
There aren’t really any large scale manufacturers making a 8.6 BLK Factory Rifle yet, however, if you jump on the waiting list now, you may be able to snag one of the early ones when they become available soon from Q and Faxon firearms, or you can even just buy a barrel conversion from them if you already have a Fix by Q.
The other manufacturers should jump on the band wagon offering 8.6 BLK chambered barrel pretty soon after Hornady starts making the brass available, and you can even have your own build on a .308 bolt face, standard-length action, by chambering a .338 / 8.6mm barrel in it once reamers become available (just remember the tight twist rate needed to make the most of this cartridge).
8.6 BLK Twist Rate
Very fast twist rates like 1:4 and even 1:3 are used for the 8.6 BLK, as this provides greater energy at supersonic velocities, and greater accuracy at subsonic velocities, thus enabling the use and stabilization of such long and large bullets out of such short barrels. The fast twist rate, also ensures good bullet expansion even at slower velocities.
8.6 BLK Ballistics
When loaded with a 210gr Barnes TTSX bullet at a conservative 2000fps from the short 16″ barrel, you still have over a 1000 ft/lb energy on target at 375 yards, although this round is not really made for such long distances. The designers also claim that the normal energy on target figure is not applicable as the incredible rotational energy of the projectile spun at such a high speed because of the 1:3″ twist rate, multiplies the energy on target, see this video to show that.
EDIT: Ballistic figures, chart and graph was updated in June 2022 to get closer to actual achieved muzzle velocity figures now that the round has been tested more, and showing that the initial muzzle velocity figures claimed by Q were a little overstated.
8.6 BLK for Hunting
Although very practical as a new do-all military cartridge, hunting is where the 8.6 BLK really shines. It redefines the general purpose hunting and utility rifle genre. Even during testing and R&D hunts, Kevin Brittingham and the guys from Q have been making waves online with their small Fix 8.6 BLK taking down everything from smaller CXP1 sized animals like a Black Backed Jackal, CXP2 sized game like deer, CXP3 sized animals like a large Kudu bull, all the way through to the very large and thick-skinned CXP4 sized African Cape Buffalo. Proving the versatility of the cartridge and rifle platform for a single, compact, do-it-all hunting rifle.
8.6 BLK Barrel Length
8.6 BLK vs .338 Federal
Most people that first read or heard about the 8.6 BLK, quickly asked why, given the similarity or superiority (as they thought) of the already available .338 Federal cartridge. Well, the 8.6 BLK is the quieter and more efficient version of a .338 Federal, basically with a trimmed back case and improved shoulder so you can get longer heavier subsonic bullets than you can with the .338 Federal. Overall it’s a more efficient and versatile design than the .338 Federal.
Whilst the case length of the .338 Federal is 2.015”, the 8.6 BLK case is 1.685” in length, allowing the ability to run heavy subsonic loads, 280 to 360 grains or more, whilst the longer 338 Federal case will put the ogive of those long projectiles back inside the case, which will perform badly.
Although having a smaller case capacity, the 8.6 BLK offers more consistent ignition of the powder thanks to more case fill, which gives you more consistent performance, especially with those heavy subsonic loads. Another big upside due to the shorter case and cartridge length, the 8.6 BLK will feed out of .308 Winchester length magazines, allowing greater compatibility. Even the fact that the 8.6 BLK uses the same bolt face as the .308 Win, means you can change your barrel on your Fix or other current rifle and have your own 8.6 BLK.
Lastly, when looking a long bullets like the Berger 300gr Hybrid with a nose length of 0.955 inches, but the case to OAL length of the .338 Federal is only 0.785 inches, meaning that those bullets or similar cannot be reliably fed from a magazine, whereas it can in the 8.6 BLK.
