Tag Archives: 308 win

Are Subsonic Cartridges Superior?

March 16, 2025blog300blk, 308 win, 338arc, 8.6blk, silencer, subsonic, supersonic, suppressor, velocitycoldboremiracle

Introduction

More and more often, we are seeing interesting developments when it comes to bullets and ammunition. Today I wanted to discuss an interesting situation regarding velocity of bullets, and how specialty designed slower cartridges are changing the future of shooting. Are subsonic cartridges superior? Well, depending on your purpose they just might be.

The velocity of a bullet when fired from a firearm has a lot to do with its utility and purpose. Most rifle bullets travel at supersonic speeds, that means they travel faster than the speed of sound. Conversely, many handgun bullets travel near or below the speed of sound. For the most part, this has been a result of typical construction limitations for both firearm and ammunition manufacturing. Handguns typically have less room for large powder capacity cartridges, which is why they are typically slower. Which is also why rifles often have much higher velocities, as rifle cartridges often have more room. Additionally, rifles need greater range than most pistol cartridges, which has resulted in their design for more velocity.

typical pistol cartridges (left) with a couple rifle cartridges (right). Even though all these cartridges have similar bullet weights, the velocities are around double from rifle rounds.

What is the Speed of Sound?

The speed of sound is determined by how fast a sound wave travels through air. We have all witnessed curious situations where we see something far off before we hear the sound. That is because the sound takes much longer to get to us than the light reflecting the image to our eyes.

To add another layer of complexity, not all air is the same. The speed of sound is relevant to the current atmosphere the sound is traveling through. Humidity and air pressure can greatly effect air density and therefore the speed of sound will change depending on the atmospheric conditions. For example; warm dry air will result in a higher speed of sound than cold humid air.

Moist air has visible effects as well as invisible effects

Why does this matter? Because bullets also travel through air, and they are also equally effected by atmospheric conditions. As a bullet travels through the air it encounters resistance, and much like a boat traveling through water, once it starts moving fast enough it creates a wave. The pressure wave caused by bullets traveling faster than the speed of sound creates a sonic boom. This is why even when using a suppressor, most rifles are still quite noisy. Because the bullet itself is breaking the sound barrier which is quite loud. The suppressor removes most of the noise caused by the report of the rifle, but the supersonic bullet causes its own noise.

This image shows both the sound waves caused by the bullet, as well as the waves coming from the unsuppressed muzzle

Subsonic bullets, those that travel below the speed of sound do not create the pressure wave or sonic boom. Much like a boat that idles across a lake doesn’t make much of a wave. And if you use a suppressor to remove the report of the firearm, these bullets can be fired pretty quietly. Almost like you see in the movies, just less stupidly.

Why would you want Subsonic vs. Supersonic?

Subsonic shooting with a suppressor can be very fun, and extremely useful if you are a hunter. Shooting a whole pack of coyotes could be doable with marksmanship and such silent shooting. The appeal of this covert shooting ability has enticed many shooters and engineers alike. Which has resulted in various new firearms and ammunition lines that are specifically designed for this purpose. Cartridges like the .300 Blackout and 8.6 Blackout have received a great deal of attention lately as suppressor use has skyrocketed. The use of these cartridges with a suppressor has made super silent shooting a reality, and it has become very addicting to those who practice it.

Culling some pest turkeys in suburbia is better done suppressed and subsonic, this was done with the **TX22** and a **Silencerco suppressor**

It is important to understand the limitations of these specially designed products. There are ammunition lines and even cartridges that are specifically designed for subsonic use. Purpose built subsonic cartridges and bullets tend to have more limitations because of velocity. In order to maintain their speed below the speed of sound there are few ways to add energy other than increasing the size of the bullet. Some folks like those at Discreet Ballistics have designed solid copper expanding bullets, to increase the transfer of energy on impact. Another theory though disputed by some; is that increasing the rotational speed of the bullet can add energy on target. This is achieved by using fast twist barrels like one-in-five, one-in-three or even as fast as one-in-one twist barrels.

The lower velocity of these bullets can greatly alter the effectiveness of them at extended distances. While it can be done, subsonic cartridges are much more susceptible to variations. And those variations are more pronounced as you cover more distance. The anonymity of super quiet shooting can be very valuable, but requires an extra level of understanding to know when and where it can be applied effectively.

This buck fell to a single shot from a subsonic 450 Bushmaster, a **405 grain solid lead-cast bullet** with a flat meplat. The sound of the bullet impacting the deer was much louder than the gun going off. My **Desert Tech MDRX**

Standard Cartridges Too

Standard cartridges can also be down-loaded to subsonic speeds, particularly those that aren’t that fast to begin with. I used to load my 308 down with subsonic 220 grain bullets, and they were fun, and quite useful.

My **Desert Tech SRS** A1 Covert with a 16″ 1:3 twist 8.6 Blackout barrel and **Anechoic suppressor**

I’ve also loaded my 450 Bushmaster down to subsonic speeds and increased the bullet weight significantly for added performance. There is an added benefit to this scenario, a 308 can shoot subsonic bullets much like a 300Blk, but it can shoot much better when loaded with supersonic ammunition. A subsonic 220 grain bullet fired from a 308 chamber vs. a 300Blk chamber will fly the same all else being equal. But say you want to increase your energy on target and distance by changing bullets and powders for supersonic use. A 165 grain bullet fired at supersonic speeds from a 300Blk will be nowhere near as fast as one fired from a 308 chamber, all else being equal.

Its easy to see why the 308 Winchester (top) can achieve much higher velocity than the 300Blk (bottom) when both are shooting supersonic 150 grain bullets

What Not to Do

Many manufacturers have jumped into making firearms chambered for some of these dedicated subsonic cartridges. And that has resulted in a great deal of adoption by folks from every walk of life. It should come as no surprise that some are shooting dedicated subsonic cartridges and ammunition through firearms without a suppressor. While they are perfectly happy doing it, they certainly aren’t getting the bang for their buck. Shooting unsuppressed with subsonic cartridges like the .338 ARC or .300BLK is like wearing flip-flops to go hiking. The greatest asset of these cartridges is shooting silently with a suppressor, so if you aren’t going to use a suppressor, why cut your velocity, energy and range for no gain? Perhaps you might have another reason, but anything you can do with a subsonic .300Blk can be done better and for less with something like a 5.56 or 6ARC. The best advantage of the Blackout is its silent shooting, so if you’re going to shoot loud, you may as well shoot something better.

This fox was far too brave, walking between us in camp in the dark. A subsonic 308 quietly put him out. And later that day, the same rifle (different ammo) was used to shoot a cow elk 200 yards away.

The Right Application

As you might have gathered by now, there is a perfect application for subsonic shooting. A scenario where you need exceptionally quiet shooting, whether that be dispatching pests or something else. For example; a subsonic 22lr is great for taking out rats covertly in the dark. And if you use the slightest bit of imagination you’ll come up with other ideas. It is these specific scenarios where a subsonic cartridge is superior to supersonic options.

Suppressed subsonic 22 pistols are very handy for dispatching pests, this one is another **Taurus TX22** with a **YHM Phantom** suppressor

Bergara B14 Crest Carbon Rifle

October 12, 2024Product review, Shooting hardware308 win, b14, Bergara, crest carboncoldboremiracle

Introduction

Towards the end of summer every year, my attention turns towards hunting rifles. The excitement of hunting big game in the cold and often snowy mountains is an awesome adventure I look forward to every year. For me, one of the main focus points during hunting is on the rifles we rely on. Today I bring you a rifle worthy of these rugged Rocky Mountain hunts; the Bergara B14 Crest Carbon rifle, chambered in the very popular 308 Winchester.

The Crest Carbon rifle incorporates a great deal of Bergara’s technological advancements. And most of those features help make this rifle an exceptional hunting tool. Today we are going to take a deep dive into both the rifle and the mountains it was meant to traverse. We’ll see how the Crest Carbon rifle stands up to heavy use, long hikes, sharp shots, inclement weather and accurate field shooting.

The Bergara B14 Crest Carbon Rifle

There are new features to the Crest Carbon rifle, but it is still built around the very popular B14 action. Bergara has done a very good job perfecting the Remington 700 footprint through their B14. It incorporates nearly all the benefits, and brings additional features and quality to the most popular design in use today.

Additionally, Bergara’s Cure Carbon barrel is used in this rifle. The Cure Carbon is an advanced technological design that uses both carbon fiber wrapping as well as a stainless steel mesh to wick heat from the bore.

As if that wasn’t enough, the rifle uses Bergara’s own carbon fiber stock. The Crest Carbon rifle stock uses a carbon spine to maintain rigidity, surrounded by hand-laid carbon fiber. The lightweight stock is both handsome and effective, with dual sling studs up front as well as QD flush cups mounted in the key spots for your sling.

The rifle is available in a variety of calibers from .223 Remington up to 300WM, and barrels lengths vary from 20-inches up to 24-inches. Barrel lengths and twist are optimized for each of the various calibers, but all of them use AICS style magazines. They also use Bergara’s adjustable trigger which is a fine option in my experience.

Continue Reading Here

One of my kids used the Crest Carbon to take his second buck. In the whipping wind at 8000 feet, we put the sneak on this little buck. Closing the distance over steep terrain. With his rifle a top the tripod, he let one shot loose from the Bergara and put a DTM 175 gr 308 Round through the boiler room.

Packing out both the deer and the rest of our gear, it was nice to have such a lightweight rifle like the Crest Carbon.

Bergara crest carbon 308 win — the Crest Carbon rifle suppressed by the **Banish Buck 30 suppressor**

Bergara B14 Crest Carbon — the extremely popular **AICS magazine system** is a perfect fit for this rifle

If you like this rifle be sure to read more about carbon fiber firearms here

bergara b14 drest carbon — the Crest Carbon is a perfect companion for a big game hunt

group 308 win — A typical group from the rifle using **Hornady American Whitetail ammo**

Top Five Cartridges For Long-Range Shooting

June 24, 2022blog25 creedmoor, 257 Blackjack, 300 win mag, 300norma magnum, 308 win, 338lm, 6.5 creedmoor, cartridges, long range, long range shootingcoldboremiracle

Top five you say? What kind of maniac could narrow it down to just five of the best cartridges? I mean the world is littered with spent casings from countless different cartridges that offered something that another didn’t. So to avoid being labeled as that guy, I am instead going to go over the process by which anyone can select their top performers as it applies to their shooting. And how I did it for myself. Today we will discuss my top five cartridges for long-range shooting.

The first step in this process would be to know and set your limits. Unless you’re Elon Musk you probably can’t afford or build a rail gun for your weekend shooting exchanges, so obviously there is a budget to keep. And if you live in flat country where the furthest you can see on a clear day is five-hundred yards. You will have very different needs than someone who lives in mountains ranges where one-thousand yards is just to the next turn in the trail. Another important consideration is the target. Hitting paper or steel is much different than meat and bone. So it’s very important to define your needs properly, both ballistically and financially.

Extremist Need Apply

If your goal is extreme distance competitions like King of 2 Miles, then you are going to want something big. My experience here is minimal. However there are many marksman shooting these distances with a cartridge I am quite fond of and my choice for extreme distance. The 375 Chey-tac, or something similar to it. The cartridge is perhaps the most common in big-bore ELR shooting, as the ammunition and components are plentiful. Not only that, it is an outstanding performer.
With high performance bullets like the Cutting Edge MTAC or the Warner Tool Flat-line, you can shoot distances that most people have never considered possible. Of course all this comes with significant cost. And perhaps an above average level of dedication, but how else could you call yourself an extreme shooter?

The **Desert Tech HTI in 375 Cheytac** is an excellent ELR rifle, matched here with a US Optics 25X scope

Okay, Maybe not that extreme

If your goals are perhaps a little more mainstream, and you don’t feel like spending $10-$20 every time you pull the trigger. Let’s talk about a better fit for you. Shooting a mile or less is much more common than it was even ten years ago. One of the reasons it has become so commonplace is the proliferation of the venerable 338 Lapua to so many affordable rifle platforms. But that’s not the cartridge I was about to recommend, I was about to say the 300 Norma Magnum. Why the 300 over the 338 you might ask? I’ll explain.

**Click here to see the 300 Norma in elk hunting action**

300 Norma ballistics when using high ballistic coefficient like those available today, will rival those of the 338 Lapua. There are pros and cons either way between the two, as far as barrel life, recoil, and even suppressors if that’s your thing. High quality bullets loaded in the 300 Norma make it a devastating long-range performer. Whether you are shooting targets, big-game hunting, or anything else. I prefer the more slender and faster fired bullets in the thirty-caliber as compared to the heavier and a bit slower thirty-three caliber bullets of the 338LM.

The 300 Norma will easily shoot to a mile and beyond, handily take down any North American animal. Additionally it has a huge selection of bullets and ammunition selections of the highest quality.

A Poor-Man’s 338 Lapua

Many years ago, before I had experienced both the 338 LM and 300 NM, I found myself in quite a quagmire. I wanted a new barrel for my Desert Tech SRS that would allow me to shoot comparable ranges to those cartridges (1700-2000 yards) , but I was but a common man.

I had nowhere near the money to feed a Lapua or a Norma, which is no small cost. Buying a barrel is one thing. But coming up with all the ammunition components needed to become proficient and shoot as frequently as I do is another entirely. So I began a study to find a suitable replacement, a champaign cartridge on a beer cartridge budget so to speak.

What precipitated from my numbers evaluation, was this; a very high BC bullet in the 7mm (.284) caliber is comparable to the BC of the bullets commonly loaded in the 338LM. So if I could get them up to comparable or better speeds, I would find myself shooting Lapua distances on Remington resources.

The 7mm SAUM

After some careful market evaluation, I was quoted a build for a 24″ 1-8 twist barrel chambered in the mighty 7mm Short Action Ultra Magnum (7SAUM). And before I knew it, my poor-man’s Lapua was in my hands. I had done all my prep work before-hand, and I had loading components ready to go.

I ended up shooting the Sierra Bullets 183 Match King, which has a very high BC. My new barrel would launch them at a magnificent 3050 feet per second (FPS). After spending a few seasons hunting with the 7SAUM, I was completely convinced I had made a good choice for the times. My SAUM shooting the 183’s actually shot flatter than the mighty 338 out to around a mile. The energy on impact wasn’t as high obviously but I wasn’t planning on hitting anything besides steel at those ranges. Even so, the SAUM retained more than enough energy to take down an animal as far away as 1000 yards, so I was certainly in good company.

The popularity of the 7 SAUM has waned some with the passage of time, another more popular choice with many of the same qualities is the 7 PRC.

Two elk taken down by a single shot from the 7SAUM, at 900 and 500 yards respectively

Lets Get Common

Nothing I’ve mentioned above is particularly common, or very cost effective for your average shooter. Sharp marksmen have been shooting significant distances for a very long time with everyday cartridges like the .308 and 30 06. And with proper bullet selection and load development, you could certainly continue on that fine tradition. Or you could embrace something more contemporary.

Go ahead and light your torches, sharpen the pitchforks, and prepare your best effeminate insults because we’re about to use the “C” word. Just prior to the current ammo crisis, the 6.5 Creedmoor has infiltrated nearly every little ammo shelf across the country. And for good reason.

The 6.5 Creedmoor

The 6.5 CM offers 300WM ballistics with recoil and cost subordinate to even the 308 Winchester. There is an extremely high-quality components and ammunition selection for the 6.5, and its easy to load and shoot. There is so much to like about the cartridge, it begs the question why it is the subject of every sophomoric and unsophisticated insult the internet has to offer.

excellent Creedmoor performance can be had from a simple setup like this **Ruger American Gen2** and **Maven Scope**

Personally I believe it to be its own worst enemy, unfledged shooters are easily tired of hearing how great the Creedmoor is. Especially since what they choose to shoot is obviously better because they chose it, at least that’s how they feel.
Do not discount the Creedmoor, it is what it was built to be; a great shooting cartridge for those first thousand yards. A great deer hunting cartridge, and anything similar to those two disciplines. It can be found nearly anywhere ammunition is sold, making it a strong contender on this list.

These 129 grain Cayuga bullets perform exceptionally in the Creedmoor, read more about them here

Out of Left Field

My tastes have changed, and my budgets matured, so I’d be remiss to omit my latest favorite. I wasn’t sure whether to put it in my list or not, due to the obscurity, but this is my list so I’ll do it my way.

Wildcats are a little different, like fingerless gloves at the range, or guys who wear fedoras. Wildcats if you didn’t know, are illegitimate children of the cartridge world, derived from other cartridges. They are either “necked up” or “necked down” and usually “blown out” to create a whole new cartridge. Many of our best cartridges were born this way, and to that list I add this one of my personal favorites.

The 257 Blackjack

The 257 Blackjack is a cartridge formed by shortening the SAUM case. Changing the shoulder geometry, and necking it down to twenty-five caliber. Simple enough, but the crown jewel of the cartridge is another very high BC bullet built by Blackjack Bullets (designer of the cartridge). The 131 grain bullet has a .340 BC, which is nearly untouchable by anything comparable in size and price. Nearly none of the 6.5 and 6mm bullets that would give the Blackjack a run for the money can. Especially when shot from the 257 Blackjack cartridge.

Blackjack has since closed, but the 131gr bullet is still made by Sierra.

From my 24” barrel the muzzle velocity is 3270 FPS, and with that impressive .340 BC you can imagine the extremely flat trajectory. There are also other high BC bullets available from Berger andHornady that have a predictably outstanding performance

This little short action cartridge will reach a thousand yards with less than 5 MRAD of elevation. And when it gets there it will still be packing well over a thousand pounds of energy and more than 2200 fps. It doesn’t go subsonic till well beyond two-thousand yards. Making it very competitive in the same ranges as the 338LM and 300 NM mentioned above.

My wife took this pronghorn doe with the 257 Blackjack, seen here with the **US Optics FDN25X**

Would I recommend the 257 Blackjack for long-range shooting? Not at the moment. The tediousness and dedication it takes to run a wildcat cartridge like this is probably more than most would care for. But should factory made brass become available, this would be a shoo-in for anyone interested. It is truly an amazing little cartridge.

Conclusion

So there you have it, my list of my top five long range shooting cartridges. You may take them or leave them, and you wont get any argument from me. Every shooter can decide what works best for his/her needs, and create their own top five.
The good news is that there are so many great choices. Despite my little list of cartridges, I could probably make due for the rest of my life with just a plain jane 308.

-CBM