#300blackout

I have been a huge fan of the .300 Blackout cartridge! For anyone that’s actively in the suppressor game, a rifle cartridge like the .300 Blackout is a no brainer. Yes I do realize that many pistol calibers can be ran subsonic in AR style rifles and pistols, but the .300 Blackout shares all of the common parts of its 5.56 counterpart except the barrel of course. This makes the .300 Blackout make much more sense than a pistol caliber AR that uses a bunch of different parts and more chance of not running correctly. Late last year I cobbled together yet another .300 Blackout from some parts I had leftover form previous projects and picked up the remaining needed parts from Brownells. My Brownells BRN-180 .300 Blackout has been one of my favorites as well. This makes the 4th .300 Blackout I own, so there’s no mistaking that I’m a fan of the caliber. But is it still the KING? 

In the past few years there’s been a number of other newer calibers coming into the market that are kinda following in the .300 Blackout’s footsteps. One of those is the 8.6 Blackout caliber that was developed by Q. This is of course a larger .338 diameter projectile than the .300 diameter projectile used in the .300 Blackout. The parent case is also that of the 6.5 Creedmoor. Barrel wist rates are considerably different as well. Most .300 Blackout are 1:8 twist and the 8.6 Blackout is a 1:3 twist rate to get the most out of the shorter barrels and heavier projectiles. The 8.6 Blackout’s advantage is the availability of much larger weight projectiles and therefore a more devastating effect on the intended target. The disadvantage in my opinion is the need to use an AR-10 sized receiver increasing the overall weight of the firearm. There’s no free lunch as they say, so you can’t gain something without giving up something else. And if you think that .300 Blackout ammunition is pricey, you’ve not taken a look at the 8.6 Blackout yet. But wait there’s even another newer cartridge on the horizon that claims to beat out both the .300 Blackout and the 8.6 Blackout. 

Introduced by Hornady is the new .38 ARC which is supposedly bale to deliver over one and a half times the energy of the .300 Blackout. Once again the advantage of this particular caliber is the ability to load with bullets much heavier than .300 Blackout. With over 300 grains on tap, the .338 ARC eclipses the maximum 225gr loads of the .300 Blackout by a huge margin. The .338 ARC uses the same pattern magazines and bolt as the 6.5 Grendel and doesn’t require the use of the larger frame AR-10 receiver to run. This is literally the best of both worlds with subsonic performance of the .300 Blackout, 1.5X the energy and the ability to maintain a similar weight of the firearm. Since the .338 ARC is totally new, only time will tell how much it takes off. As expected the ammunition is out of this world expensive at the moment, but if popularity takes off, expect the prices to come down a bit once supply matches demand. 

So is .300 Blackout still the subsonic king? I’d say for now due to the popularity and availability of the caliber, but be on the look out for these 2 other new calibers, especially the .338 ARC. Brownells has you covered on all 3 of these calibers if you’re looking to pick one up.