257 Blackjack | Coldboremiracle

If you’ve followed me for very long at all, you must know by now that hunting is my greatest passion. Its become a way of life around my house, and sharing it with loved ones brings me the greatest satisfaction. That said, the hunting lifestyle doesn’t always enjoy the positive public reflection it once did. A great fear of mine is the loss of our hunting opportunities due to the growing anti-hunting sentiment around the world.
I have worked diligently over the years to effect what I think is the silver bullet to that argument; getting more new hunters addicted to this incredibly rewarding lifestyle.

Today’s story is about my latest efforts, and how patience and love created both a new hunter, and a whole new family bond.

Watch the video at the end of this article

Last year I convinced my wife to get her hunters safety, she grew up in a non-hunting family and environment which made it unnecessary. She made short work of the class, and last fall was her first time to ever go hunting with me carrying a rifle and a tag in her pocket. Unfortunately she never got a shot despite her valiant effort and hard work.

Fast forward to September 2020, and again we prepared for The hunt. This year she was lucky enough to draw a pair of Wyoming doe antelope tags, one of my favorite hunts precisely for new hunters like her.
We prepared all the gear we would need, and set out well before sunrise to get into a good position to spot animals as the sun came up.
Typically from experience, Pronghorn (their proper name) aren’t hard to find in Wyoming, they tend to begin activity after sunrise, keeping their sharp eyes on anything that moves on the wide open plains they inhabit.
After looking over several rolling brush covered valleys, we spotted a small group of antelope on the edge of the next rise. Trying to cover distance quietly and quickly can be a challenge with a new hunter, but Mrs. Coldboremiracle was keen to follow and do all the right things. We soon found ourselves on a windswept rise, looking in the direction the antelope had gone. The wind howled and gusted as we glassed the area, we quickly picked out the bright white sides of the herd. The smaller group had just joined a larger one, probably twenty-five animals. A few bucks, does, and a bunch of fawns.
We hunkered down, out of sight, even though they were nearly half a mile away they would easily spot us and sprint into the next county if we weren’t careful. We surveyed the whole area, and decided to try and put a stalk on the large group. Normally that many eyeballs is not a great choice to try and put a sneak on, but we had a line of cedar trees between us. We discussed the other options, and the idea of using the trees for concealment to get closer seemed like the best option.

The weapon of choice that day was my 257 Blackjack custom, a SAUM based wildcat shooting the Blackjack Bullets 131 grain Ace. It is a ballistic gem, providing extremely flat trajectories, and ignores the wind as much as any bullet can.

With rifle in her hands, we snuck down into a wash and towards the line of trees. Stopping to look at the herd every few steps to see if we’d been spotted yet. I breathed a sigh of relief as we finally made it behind the first tree, giving us the concealment the open prairie would not. The wind continued to gust, it felt like anywhere between 10 and 25 miles per hour. The noise of the wind gave us plenty of sound cover, all we had to do was stay out of sight within the trees as we worked towards a spot we could get a good shot.
We worked our way south, with the wind blowing hard in our faces. After about four hundred yards of sneaking, the trees began to thin, and we could see the herd slightly above us and four-hundred-fifty yards away. After confirming that we had not been detected, we crawled around to the shady side of the last small cedar that would give us cover. While I watched through the spotter, She crawled out onto her belly on the soft grey dirt behind the Blackjack. With the distance confirmed, and everything in position it was time to get noisy.

The sixth-sense that animals have must have been working hard that morning. First one, then several others looked straight at us, perhaps having seen some of our final movements. Their body language was concerned, but not spooked. So we focused our attention on a mature doe who stood out from the group. She was quickly obscured by the group however, a challenging aspect of these animals. They ball up in a group making it difficult To get a clean shot.
We ended up having to shift focus to another doe, who stepped slightly out of the group facing the opposite direction. It had only been maybe thirty or forty-seconds since we got into position, but the buck in the group began herding them towards the next rise. Clearly they knew something was up, I told Mrs. Miracle that it was now or never. The buck was moving towards her at the back of the group to push them over the hill and out of sight. So with her heart pounding and the wind whistling by, she pressed the trigger.
The 257 Blackjack runs just over 3200 feet per second, its blistering speed matches its flat trajectory. The 131 grain Ace zipped through the doe in less than half a second, with over 2300 pounds of energy, the bullet was probably still dry as it hit the powdered dirt behind her.
The whole herd scattered from the impact, but our doe had been pointed the opposite direction from the rest. She ran about fifty-yards, before she slowed down, and began to stumble. She laid down and her head swayed before keeling over in the dry prickly brush. The rest of the herd stood in the distance, apparently waiting for her to catch up.
Back at our shooting position it was all smiles and excitement, we quickly packed up and began the walk towards our prize.

The Ace had passed just behind the shoulders, perhaps a little higher than one might recommend, but it worked out to be perfect. It passed through without even touching a bone, so almost zero meat was lost from the shot, a perfect double lung shot.

We took pictures, and savored the moment before cleaning her up, and transporting her back to the truck. I remember on several occasions during the stalk, as well as in the final moment before the shot, I had to remind myself that this was a new hunter. The perspective of a new hunter is not the same as an old hand, it requires a little bit of discipline.

Keeping the moment fun, and trying to suspend the pressure as much as you can, will make the experience more fun for those that are new to it. Keeping calm is tough for me, I get wound up pretty tight in the heat of a hunt. But I found that staying calm, and ensuring that she was comfortable and ready made it a better experience for everyone.
As we returned home with her prize, we spoke about it. She is already excited for our Mule Deer hunt that starts in a few weeks, and next years antelope hunt. It is possible, that I’ve hooked her for life now, all according to my plan…

-CBM

Pit Boss Build Specs
-Remington 700 SA
-Proof Research Carbon 7.5 Twist 25 cal 24″
-US Optics Foundation 25X JVCR
-IOTA Carbon Fiber Stock
-Hawkins Precision Bottom Metal SA AI
-Trigger Tech Diamond Flat Shoe
-Blackjack Bullets 131 Grain Ace
-Machine Work done at ES-Tactical

You may have read my piece on the 25 Creedmoor from a while back, if you haven’t then make sure you go read it after this. In that article about the 25 Creedmoor, I detailed how my nascency in precision rifle shooting began with a twenty-five caliber rifle, and that I had returned again to the quarter-bore. There’s more to that story, however.
One of the main reasons I quit shooting that old twenty-five 0’six, was because there was never a good bullet selection for it. The biggest bullets available were one hundred twenty grain, and they were hardly long-range bullets, with ballistic coefficients not much better than anything else designed in the sixties. That was all about to change, and change for the better. I couldn’t have known how far down the quarter-bore hole I was going to fall when I first made contact with Blackjack Bullets.

The 257 Blackjack next to its larger parent, the 6.5 SAUM

That first conversation I had was with Miles Johnson, the brains behind Blackjack Bullets. Like me he had often hungered for a better bullet for twenty-five caliber cartridges, but he had the intellect and drive to do something about it. Miles is a smooth-talking guy, with very unequivocal purpose in conversation. The kind of guy you could sit around a fire with a bottle of whiskey and watch the stars, and before you know it he might be talking so deep about drag and aerodynamics that you have to start reading the bottle to find words you understand.
Our initial contact began my twenty-five Creedmoor project, Miles’ company Blackjack Bullets was producing the 131 Grain Ace bullet, and I intended to make it the crown jewel of the project. Which has been an extremely superior performer for me lo these short two years, it leaves its six-point-five cousin in the dust. But Blackjack had been working all along on something even more threatening and treacherous, it was their own cartridge that was purpose-designed to make the 131 Ace sing a tune that nobody could touch. That project was the Two-fifty-seven Blackjack, a short action magnum cartridge based on the SAUM case. It would fit in short action rifles, feed from AI patterned magazines, and push the Ace beyond thirty-two-hundred feet per second. It falls somewhere between the old 25WSSM and the 25SAUM wildcat.

The 131 Ace has an advertised G7 BC of .330, my personal experience and testing led me to believe that number is a tad conservative and that the number is more like .340. With an immaculate profile like that, the Ace when launched at these speeds is as flat as most available cartridges you can get, and it cheats the wind from its deviant influence.
Since the twenty-five Creedmoor had been such an outstanding success, I decided that I must indeed have the two-fifty-seven Blackjack as well, I figured it would be an amazing Rocky Mountain hunting rifle. So as soon as Miles had a reamer, we got started on the project.

The Pit Boss. Sporting a 24 inch Proof Research carbon wrapped barrel, and a YHM suppressor adorns the muzzle.

With weight in mind, I decided I would spend the extra cheddar and get a Proof Research carbon fiber barrel with a 7.5 twist. My 25 Creedmoor is a 7 twist, but with the much faster Blackjack I needed a slightly less agressive twist. It was matched to a lightweight carbon fiber stock from Iota Outdoors. Both would be connected with a simple Remington 700 short action. I swapped the factory trigger for a superior one from Trigger Tech, this has been a pretty standard practice for me. On top I mounted my US Optics TS 20X, which I think is perfect comapnion for this lightweight but long range hunting rifle. That said, I have a USO Foundation 25X on the way that might go for a ride on the Blackjack as well.

Trigger and magwell detail, all a perfect fit.

Next, it was time to start load development. Which requires making brass from something else, the easiest seemed to be Hornady 6.5 4S cases, they were cut, sized, annealed, then cut again, sized again, turned, and annealed. The finished product is a beautiful fat and short little case, it looks like the X47 after an all you can eat 24 hr buffet.
Mine is only the third rifle chambered in the Two-Fifty-Seven Blackjack so load data was based entirely from what Blackjack bullets had tried in theirs. I tried several different powders, including H4350, H4831SC, but I ended up getting the best velocity with Alliant RL 26. With 56 grains of powder, I was getting just shy of 3300 feet per second. Fireforming these fat little cases gave some slight variation in velocity, but that didn’t surprise me. I did quite a bit of testing with loads back and forth, which is a tedious process with such a limited supply of brass in which I was so heavily invested. Magnum primers seemed to give the cartridge too much of a pressure spike, and excessive wear to the cases, so I backed down to just a Large Rifle primer, which significantly softened the blow. This change still gave me adequate velocity, but also saved my brass from being ruined prematurely, and eased in extraction from the chamber. The Ace likes to run right around 3200FPS from the Blackjack, and that’s just fine with me.

A typical group from the 257 Blackjack, including a true coldbore shot (left) and four followup shots.

With no shortage of space here in the Rockies, I decided to get the Blackjack out to some significant ranges. I wanted to see how well my projections panned out, and see how close the trajectory lined up with my ballistic computer Trasol. My first distance conquered was 1025, this after confirming a fairly rough zero in the dirt at 150 yards. From there I dialed the indicated 5.3 MRAD, and closed the bolt. One of my favorite things about shooting that far, is the nice delay you have to get a good clear sight picture to watch the impact. The first impact was a touch low, so I corrected the .2 and fired again, making perfect elevation on impact. I then shot it at 1250 yards where it was slightly ahead of the predicted dope, and I had to dial back down half a MIl to get on target. I then stretched it out to just a few hundred feet shy of a mile, and 12.8 MRAD was just the ticket for that range. For the naysayers, that is two MIL’s ahead of the 220 grain 300 RUM I was testing a few months back. And at 1600 yards, the Blackjack is 300FPS faster than the RUM, and only 60 pounds of energy less than the RUM. These are of course estimations made by my ballistic calculator, but they appear to be spot on based on the data I’ve shot to within a reasonable margin of error.

Shooting these 25 caliber heaters through this carbon wrapped barrel can heat it up quick. This rifle was purpose-built to be a hunting rifle, so barrel heat is of little concern. Rare is the occasion that I shoot more than a couple shots, so the weight savings are far more valuable to me in a hunting rifle.

The recoil on the Blackjack is not bad at all, but for a short action I would call it sharp. Obviously, there is going to be some kick from something this spicy, but its certainly not bad, I would compare it to a heavy 308 load, keeping in mind the eleven-pound rifle weight.

One of the many concerns I am hearing from people about this project is the old “barrel burner” comment.
Yep, its gonna get roasted. If it gets to 1200 rounds I’ll consider myself lucky, and then I’ll get another barrel cut and threaded and screw it on in too. That is if I haven’t found something even sharper than the Blackjack by then.
Another concern I have heard from many is about feeding. Short and fat cartridges tend to have feeding issues, especially with steep shoulders like the Blackjack. But to my gratification, I have yet to have a single malfunction. It smoothly feeds from an old beater AICS magazine, which will hold seven of these handsome dandies. Whether the first, or last round from the mag, these hop right into the chamber without any hangups. And single feeding is no problem either, if you just toss them in with a bit of forward motion, so they clear the blunt breach of the barrel, the bolt closes smoothly.

Bolt knob detail. The 257 Blackjack was initially to be called the 257 Pit Boss, I decided to honor the original name by memorializing it here.

A wildcat cartridge is an adventure wrapped in hundred dollar bills, but it is not without its fun and excitement. I am not even close to being done with the 257 Blackjack, hunting season is just around the corner, and I fully intend on putting the Blackjack’s talents to work. With both deer and elk to harvest this fall and winter, the downrange energy, and resistance to wind, this lightweight but potent little rifle is a perfect candidate for these rugged Rocky Mountains that have become my winter range. With any luck, brass will be commercially available within the next few months from at least one reputable manufacturer. Reamers and dies will also soon be available from Blackjack Bullets website, so it may not be too long before this little cartridge is made an honest one.

The Pit Boss has since received its scope upgrade, the US Optics F25X

In the meantime, I will continue to prepare and practice for the hunting season waiting for the next best thing. Miles may have some mad scientist things going on at the Blackjack Lab somewhere in the hills of Oklahoma. The best news of all perhaps is that big names like Berger and Hornady are following the lead, coming out with better bullets for the quarter bore fans like myself. So the future of the 257 Blackjack, as well as my 25 Creedmoor, and any fast twist 25 caliber cartridge will be bright and long-lived.