Tag Archives: 300 blackout

Fast Twist and Quiet Shooting: The 8.6 Blackout

May 22, 2025blog300 blackout, 300blk, 338, 338 arc, 338arc, 450 bushmaster, 450bm, 8.6 Blackout, 8.6 BLK, 8.6blk, subsonic, Suppressedcoldboremiracle

Introduction

Every so often there are new cartridges that break onto the shooting scene, most of the time it is part of a marketing campaign, but sometimes there is a higher purpose. Some new cartridges offer a marginally better performance like some extra feet per second, or a faster twist for modern bullets. But today we are looking at a bit of an oddball, in that to some folks it seems like a step in the wrong direction. The subject of discussion today is the very popular fast twist and quiet shooting: The 8.6 Blackout. A relatively new cartridge brought to us by the folks at Q LLC.

athlon Rangecraft velocity pro chronograph, Garmin Xero C1 chronograph, chronograph, comparison, review, garmin, athlon, 8.6 blackout, — the Athlon Rangecraft Velocity Pro Chronograph was used to measure velocity

Blackout Background

The bigger blackout, the 8.6 follows the same line of thinking as the popular 300 Blackout. *Record scratch* The 300 Blk has been around for a long time, first as the 300 Whisper. The cartridge has done well particularly in AR15 platform rifles. Its main idea is contrary to popular trends in ammunition; slowing bullets down to reduce the sound signature. Of course with slower velocities the only way to keep energy on target up is to increase the bullet weights used in these situations. The heavier bullets typically shot at these slow speeds, require faster than average twist.

the **CGS Group Hekate 338 suppressor** was a fantastic option to keep the 8.6 quiet

Slowing bullets down to below the speed of sound is by design with Blackouts, doing so removes the supersonic shockwave produced. And when coupled with a suppressor to remove the muzzle report of the firearm, the result is near movie quiet shooting. This is where both Blackouts shine, when they are shot suppressed with subsonic bullets, there is a level of anonymity that is appealing to many hunters.

The 8.6 Blackout

It should come as no surprise that the boys at Q came up with the 8.6, carrying on from their previous work. The cartridge is based off of the 6.5 Creedmoor case, that is opened up to accept .338 caliber bullets. Bullets typically weigh between 200 and 350 grains, again, using heavier bullets is part of increasing energy on target when increasing velocity is not an option.

Loading the 8.6 Blackout is usually done with faster burning powders typically used in pistols and cowboy cartridges. Again, this is because velocity is not the goal of the 8.6. It has a very specific purpose, to propel big bullets right up to the speed of sound but not exceed it.

I was turned onto the 8.6 Blk a few years ago, when I sat down to speak with Ian McCollum of Forgotten Weapons. As nerds often do, our discussion quickly went to numbers and the science behind 8.6 ballistics. A brilliant part of the 8.6 design that departs from the 300 Blk predecessor, is the barrel twist. Taking the fast twist for heavy bullets to an extreme, has more than just stabilization benefits. The 8.6 typically uses a one twist in three inches (1:3), yes it almost looks more like threads than rifling. This incredibly tight twist does far more than stabilize long and heavy bullets.

8.6 Blackout, 8.6blk, brass, loading, desert tech, srs, srs a1, sig sauer, tango 6

The Numbers

Let us again look at numbers, the point of the Blackouts is to keep bullets under the speed of sound. Subsonic bullets are quiet, and if you can’t increase speed the only way to increase the energy on target is to increase the mass of the bullet. At least it was the only way, but there is another. The 1:3 twist of the 8.6 drastically increases the rotation of the bullets, and as the RPM of 8.6 bullets increase, so does the energy they impart on the target.

8.6 Blackout, 8.6blk, brass, loading, 300 grain, sierra match King — The 300 gr. Sierra Match King is a great bullet for the 8.6Blk, they were provided by **Wideners Reloading supplies**

This of course only works if the bullet grossly deforms from its smooth shape. Imagine if you could, removing the blade of your favorite blender, and putting a bullet in its place. Even if you filled the blender with tomatoes, the spinning bullet wouldn’t do much. But imagine now that the bullet opens up like some are designed to do, with broad petals and increased diameter. You can imagine what this blender bullet might do to organs, even though its velocity is subsonic.

8.6 Blackout, 8.6blk, brass, loading, desert tech, srs, srs a1, sig sauer, tango 6, anechoic, anechox 35, suppressor

Popular Firearms in 8.6 Blackout

As the popularity of the 8.6 has increased, many firearm manufacturers have brought new guns to the market chambered thusly. And the volume of manufacturers doing so, seems to show some faith in the concept. It would be far too time consuming to list them all, but its safe to assume you can find one from your preferred brand. Whether it be one of the Fix’s by Q, or one of the CMMG variants, or more bargain branded guns like Bear Creek Arsenal. The 8.6 I am shooting today is like many others a custom one, a sixteen-inch 1:3 twist barrel for my Desert Tech SRS.

my **Desert Tech SRS 8.6Blk** with the **Anechoic Anechox 35 suppressor** and **Sig Sauer Tango 6 riflescope**

Of course the 8.6 Blackout can also be used as a supersonic cartridge as well. There are plenty of options out there in the 180-230 grain class that can also be used. Though my personal opinion is if you are going to shoot super sonic cartridges there are better options.

Suppressors

Shooting the 8.6Blk without a suppressor makes no sense to me, so I wanted to try a few different options to see what worked best. It should come as no surprise that the CGS Group Hekate won that competition. This DMLS suppressor is well known for its superior suppression, and it made the 8.6 sound like a distant duck fart in quiet water.

a little spread of some of my **8.6 Blk handloading supplies**

I purchased a set of dies by Lee Precision, and started trying various loads to see where the 8.6 would take me. I will say that I did find it a touch more challenging than loading the 300Blk. It took a little more work to find the right powder and suppressor combination that would produce quiet results.

Continue Reading Here

Comparing Subsonic Bullets to SuperSonic
Velocity	300gr SMK 8.6Blk	% of Loss from start	300gr SMK 338LM	% of Loss from start
Muzzle	1000 fps / 666 Ft lbs	100%	2730 fps / 4963 Ft lbs	100%
250 Yards	965 fps / 620 Ft lbs	96% fps / 93% Ft lbs	2484 fps / 4111 Ft lbs	91% fps / 83% Ft lbs
500 Yards	932 fps / 578 Ft lbs	93% fps / 87% Ft lbs	2250 fps / 3373 Ft lbs	82% fps / 68% Ft lbs
750 Yards	900 fps / 539 Ft lbs	90% fps / 81% Ft lbs	2027 fps / 2738 Ft lbs	74% fps / 55% Ft lbs

Left to Right: 300 Blk, 8.6 Blk, 450 Bushmaster, 338 Lapua Magnum. The three on the left are loaded subsonic for quiet work

Want to read about another big subsonic cartridge? Click here

CZ 600 Trail rifle 300 Blackout

June 27, 2024Product review, Shooting hardware300 blackout, Cz, cz 600, trailcoldboremiracle

Czech firearms manufacturer CZ has hit quite a few out of the park lately. Today I bring you a review of another one of CZ’s more recent ventures; the CZ Model 600 Trail chambered in 300 Blackout. The compact Trail model promises to bring compact performance, something I enjoy myself. Let’s get into this review!

Gun Specs

Model	CZ 600 Trail 300AAC
Action type	Bolt-action
MSRP	$1079.00
Chambering	300 AAC Blackout (tested), 223 Rem, 7.62×39 Soviet
Magazine capacity	Factory 10 (uses Bren Stanag magazines)
Magazine type	detachable
Stock type	PDW 4 position collapsible
Length of pull	5.8 to 13.7 Inches
Sights	Picatinny rail
Barrel	16.2 inch Hammer-forged semi-heavy, suppressor ready ⅝-24
Barrel twist	1:7
Overall Length	27-35 inches
Weight	6.1 pounds
Trigger	Adjustable
Safety	AR style

Background

The 600 series of rifles is a more recent product line from CZ. Some of the company’s other impressive rifles like the Model 550 and model 457 are extremely popular with shooters. But the 600 series appears to be broad enough to cover most purposes.

Shooters will be happy to see that the model 600 is available in a micro action (tested today) as well as a standard short-action, and long-action. This spectrum of options means there is surely a Model 600 for you.

Shop all CZ rifles

As far as I can tell, the 600 series of rifles was designed to be a modern replacement to aging designs based on Mauser’s. Something to compete in the same market as Tikka T3’s and the Ruger American. I love the classy quality of the Model 550’s, but I can understand why CZ would move towards something more efficient to manufacture.

Sometimes, modern manufacturing designs also mean cheap. For example, the Ruger American is very popular today, but I don’t think it’s as robust or well-built as the old Ruger M77. It may function just as well, and even eclipse the capabilities, but it doesn’t feel as stout as my old M77.

I’m optimistic that CZ hasn’t short-changed the model 600 by incorporating cheap imported parts and technologies. But that’s what we are here to find out. Perhaps someday there will be a collector grade Model 600 Safari hung over my hearth.

Model 600 Features

Threaded Barrel- ⅝-24 thread pattern to fit your favorite suppressor
M-Lok Handguard- Allows easy mounting of accessories
Picatinny Sight rail- for mounting sights or rifle scopes
Detachable Box Magazine- CZ Bren pattern stanag magazines for quick reloads
Adjustable trigger- easily adjusted for best feel
AR style safety- familiar feel is easily operated
Collapsible PDW stock- reduces the size of the rifle for storage or transport

Other Models

In addition to the model we tested today, the Model 600 Trail is also available in both 223 Remington and 7.62×39 Soviet. These three micro-action options give you plenty of performance choices.

CZ Model 600 Trail Review

Picking up the Trail for the first time, I wasn’t exactly sure what it was for. By that I mean its purpose. At a glance it almost looks like some kind of AR type rifle, until you notice the bolt. Once I picked it up though, and gave it a quick look it became quite apparent what this rifle is for.

With a short sixteen-inch barrel and a collapsible stock, this rifle was meant to go places. And with a name like Trail I assume CZ means for us to take it into the mountains. But to be honest, I think it would also make a good covert rifle. Something to tuck under the seat of your truck.

Using the 300 Blackout cartridge also suggests some civilian spook purposes, such as dispatching pests around the house. Or just hunting animals quietly, as the subsonic ammunition available for the Blackout is movie quiet.

Range Prep

Before heading out with the rifle, I first mounted up a riflescope. The Maven RS 3 is a 5-30 power scope, probably a little more scope than this rifle needs. But it would help test the rifles capabilities.

cz, cz 600, trail, tripod — The **Maven RS 3 riflescope** was a great fit for this rifle

Instead of the typical bipod I would mount on a rifle, I put a tripod adapter for my little Precision Rifle Solutions tripod. This would give added stability, and additional shooting positions. I grabbed a few boxes of 300Blk ammunition from Hornady and HSM, both supersonic and subsonic varieties.

I also threw a suppressor in my bag, a Yankee Hill Machine Nitro. Shooting a 300Blk without a suppressor in my opinion is silly, I wanted to experience it proper.

Shootability

Once I was on the shooting mat with the 600 Trail, I quite enjoyed shooting it. There was a few things that I noticed immediately as I did my typical process. The bolt feels great in this short little action, it took me a minute to find the bolt release because it’s on the opposite side of the rifle from where typically found.

The trigger felt great, and despite being able to adjust it I just left it where it was. Cycling cartridges through the gun felt very nice, and spent cases ejected nicely. The firm ejector spring sent cases further than I expected.

The hushed report of shots were spectacular, I could hear the bullets striking the target downrange. I loaded magazines and ran all my different types of ammo through the rifle.

It didn’t take long to find something I would change about the rifle. The collapsible buttstock is fantastic for storing the rifle, but it caused me an issue while shooting. First of all, the PDW style stock has three or four locking positions. But it only locks in one direction, meaning you can still pull it out further. This caused me a little trouble because I found the third position to be ideal for my shooting needs. But while running the bolt quickly, I found as I pushed the bolt forward it would extend the stock to the fourth position. Not a huge deal, I suppose you could dremel it out to stay in each position.

Also, the cheek rest on the stock turned out to be a little low for the scope mounting configuration. Obviously this is something I could have changed, but I would have loved if the cheek rest had been adjustable.

The rifle is very light, and easy to maneuver with its short sixteen-inch barrel. With a sling in place, it was very pleasant to haul around these mountains.

Reliability

Other than the issue I mentioned with the stock, I found nothing unreliable about the Trail. The rifle is designed to use Bren magazines which are Stanag pattern I believe. I had 10 and 30 round P-mags for testing and they worked flawlessly. They did fit a little wobbly, but that didn’t seem to affect the function, and since they aren’t Bren mags, I won’t hold it against the rifle.

Accuracy

I shot an assortment of ammunition through the rifle, the best performing ammo seemed to be the Hornady 300Blk options. The 110 grain supersonic produced groups around 1-1.5 MOA, very similar to the 208 grain subsonic loads. These results were done at 100 yards.

target — a typical group from the CZ 600 Trail

Ergonomics

The fit of the 600 Trail was better than I expected. Other than wishing I had mounted the scope lower, the rifle fit me quite well. The grip angle feels nice, and the AR style safety is exactly where you’d expect it to be. And it has a very nice little click to it.

The Trail has a magazine release on both sides of the rifle, which gives you more options. As I mentioned the bolt release is right in front of the bolt handle. And while it did work flawlessly, it felt a touch janky. It was the only thing on the rifle that made me think; “oh no CZ, don’t do that”.

The M-Lok handguard was great, and shooting the rifle supported or unsupported was fantastic. It was nice to be able to attach things to the handguard for shooting support.

Value

Searching for a CZ 600 Trail to purchase, it seems the street price isn’t far off of the MSRP. So you can expect to pay right around a thousand dollars at the time of this printing. That seemed a bit steep for me when I first saw the price. The Ruger American offers many of the same features and can be had for as little as five hundred bucks in some places. And the Howa Mini can be found for under five hundred if you can find one. It too offers most of the same features, lacking only the collapsible stock and M-Lok handguard.

Typically I give CZ a leg up over other brands, and in this comparison I probably still would choose the CZ over the other two options.

Pros and Cons

Pros

Very compact for storage and transport
Very fun to shoot
Reliable function
Easily configured to your liking
Great suppressor host

Cons

Not inexpensive
One way locking stock

Report Card

Shootability (B+) The action runs great, cycling cartridges and pulling the trigger all felt like quality I would expect from CZ. I would change the stock function somewhat though.

Reliability (A) No malfunctions were experienced while shooting the rifle

Ergonomics (B+) The rifle feels great when shouldered, everything but the slight wobble of the PDW stock and magazine felt fantastic.

Accuracy (B+) In my experience, 300Blk hasn’t been particularly accurate when compared to cartridges like the 223 or 6ARC. But the 600 Trail shot comparably to most others I have shot.

Value (B) As I mentioned, there are other good rifles that will do the same thing for less, but they aren’t CZ’s either.

Preferred Ammo

Shooting Hornady ammo certainly seemed to produce better results than others. For both supersonic and subsonic the Hornady Black ammunition provided the best accuracy and performance.

The 110 grain Black would be great for hunting deer or any other supersonic purpose. The 208 subsonic was far better for covert purposes like dispatching raccoons off the porch.

Accessories

This rifle absolutely needs a suppressor, it is made for it. I used the Yankee Hill Machine Nitro N2.0, but any good 30 caliber suppressor would work well here.
A good sling is also very handy, I used a Magpul MS1 sling which worked well.
A rifle scope is the best sighting option, while the Maven I used for testing might be a bit much, I would strongly recommend something like the Eotech Vudu 1-10.

Final Thoughts

I really enjoyed the CZ Model 600 Trail, though it isn’t really my kind of thing I can still appreciate what it does. It would be a great little rifle for a rancher to keep on his ATV or in the truck. It gives great compact maneuverability and still shoots well enough to quietly get rid of coyotes, groundhogs or whatever else you might need to blackout.

-CBM

Dead Air Sandman K

February 25, 2022Product review, Shooting hardware, suppressors300 blackout, 300blk, dead air, sandman, sandman k, silencer, suppressorcoldboremiracle

The Project

In the search for a very small and useful rifle, my brother put together a 300 Blackout pistol. Though a deeply committed rifle junkie, I’m not exactly a huge Blackout proponent but I can surely see what the appeal is. One thing I do know for sure, is that unless you are going to run it suppressed, you are leaving most of the Blackout’s magic on the table. That is where todays subject comes in, the Sandman K was selected to go with this little project, and today we’ll take a look at how it performed the task.

The Sandman

The name suggests a peaceful slumber, I interpret that to mean the Sandman at a minimum won’t cause a huge disturbing raucous. Which is exactly what the Blackout was meant to avoid.
The Sandman family of suppressors was meant to provide heavy duty service to shooters who prefer suppressed fire. Dead Air claims the Stellite and stainless construction are among the most durable materials used in the suppressor market today. The suppressor is five and a half inches long, and weighs in at just under thirteen ounces. The Sandman has a thirty-caliber bore rated for cartridges up to 300 Winchester Magnum, and it also has available end caps with 5.56 and 6.5 bores. The Sandman mounts to Dead Air’s QD nitrided muzzle devices, they boast single-hand installation and removal that is simple and fast. All this comes with a Cerakote finish for a handsome and durable service life.

Installation

Once the Blackout pistol had been finished, it was time to install the KeyMount muzzle brake. This was a little bit of a challenge because the barrel was recessed inside the handguard, and to be sure it stayed there a serious thread-locking plan was undertaken. The KeyMount design is easy to understand, but I have had a couple issues with it. It uses a three lug ratchet cap that aligns with the muzzle device, and once pushed all the way down to the seat you can twist the suppressor a couple times tightening up the entire assembly on a tapered shoulder.

The Sandman on the 300blk rifle, note **Holosun Sight and magnifyer**

I say problems, but really it was just a lack of training or getting used to the function of the Sandman. Getting the lugs lined up properly can take a few tries at first, much like a USB you have to try it the same way a couple times to get it right. Once the can is locked up though, it is solid as can be. The system is indeed quick, and strong which explains why so many have switched to it. One thing I did find, which I think can happen with many of these QD type suppressor mounts is they get quite tight to the mount at times. Particularly when whoever installed it did so with significant exertion, the suppressor can be a bit of a chore to break loose and even more so if it has been on the host for a significant period of shooting and time.
One of the great benefits of this system and again what has made it so popular and prolific is the ability to switch the suppressor between hosts quickly and easily. Having extra muzzle devices can give you a great many options for using the Sandman and others that utilize the same mounting system.

On the Range

Once the K-Man was mounted, we set to test firing the host, and adjusting the gas system for optimal operation. As you might expect from a can this small, there was a little more noise than I was used to for suppressed fire. I also noticed a fairly prominent first round pop, with an accompanying flash. Super-sonic shooting with the Sandman K was definitely louder than what I am used to, but again that is a normal and expected occurrence for a suppressor this short. K cans are typically used for different situations where maximum suppression is not the main goal of the suppressor. They are more just to take the edge off for shooting inside buildings or similar situations where massive muzzle blasts are particularly unwelcome.
Sub-sonic shooting on the other hand is much more tolerable, and the real reason the blackout shines. Sub-sonic ammunition doesn’t have the noise associated with bullets breaking the sound barrier, and the Sandman K does just enough to break up the noise produced by the muzzle-blast to make it very pleasant to shoot. And it does it while adding as little as possible to the length of the host firearm.

The Blackout and Sandman combo turned out to be a excellent pairing. Much better I think than had we run the K on a regular centerfire rifle such as a 308 or something similar. While it of course would provide some suppression, it would certainly not be hearing safe. To be fair very few suppressors are hearing “safe”, but my personal position is; I don’t collect stamps and pay money to continue using ear plugs. So for me the Sandman K is going to stick with subsonic hosts, or at a minimum with diminutive cartridges.

Get your own Dead Air Suppressor

Conclusion

There are so many excellent suppressors on the market today, but some I feel are better for niche uses. Would I recommend the Sandman K for a first time suppressor purchaser? Absolutely not. The S or L model on the other hand would be an excellent choice.
But if you are knee deep in stamps and trusts, there’s nothing wrong with having a few dedicated cans for very specific purposes or hosts. For that purpose I think the Sandman K is a bulletproof option, it is neither the first and certainly wont be the last can purchased for a calculated purpose around here. As for the little Blackout, it does its thing real quiet now.

-CBM