The popular new kid in the rifle world is the 6mm Creedmoor. It’s winning all kinds of target competitions. It’s also dropping pronghorns, whitetails, mule deer, coyotes, and even elk — and I’m not buying one.
Before I tell you why, let’s examine this magical new cartridge in detail and you can decide if you can afford to ignore it, too.
6mm Creedmoor Genesis
As its name suggests, the 6mm Creedmoor sprang from the 6.5 Creedmoor and the devious mind of my friend John Snow, gun columnist at Outdoor Life magazine. Back in 2009 John asked the engineers at Hornady if they’d neck their 6.5 Creedmoor down to make his 6mm version, and they did. The round began winning a high-speed shooting game known as Precision Rifle Series competition. Targets are engaged clear out to 1,300 yards, and the faster you hit them, the higher your score. Seeing hits and misses is important in this game, so a cartridge that will shoot fairly flat, resist wind deflection and minimize recoil is critical. The 6mm Creedmoor does that by handling extremely long, high B.C. bullet in AR-10 rifles.
Now let’s get back to the cartridge itself. As noted, the 6mm Creedmoor was hatched from the 6.5 Creedmoor, and that round is the ballistic twin and nearly identical physical twin to the 260 Remington. It’s essentially the 260 Rem. case with the shoulder pushed back a bit to lengthen the neck. The shoulder is sharpened from 200 to 300 as in the 30 TC cartridge. The result is internal volume about 5% less than the 260 Rem, but less bullet intrusion into that powder space. Both cases drive 140-grain bullets within 50 fps to 100 fps of each other.
6mm Creedmoor in Good Company
Similarly, the 6mm Creedmoor compares to the 243 Winchester. As most of us know, Winchester unleashed its 243 Win. in 1955, the same year Disneyland opened, gas cost 23 cents per gallon and we launched the world’s first nuclear submarine. The 243 Win. was and still is the 308 Winchester (detailed in this article) necked down to 24-caliber, just as the 260 Rem. is the 308 Win. case necked down to 26-caliber, albeit with a slightly longer body to prevent accidental chambering in 243 Win. rifles.
As you can figure out, all these similarities suggest the new 6mm Creedmoor should perform about like the 243 Winchester. It does. Both cartridges throw 100-grain to 108-grain bullets about 2,950-fps to 3,000 fps MV from 24” to 26” barrels. So will the old 6mm Remington (circa 1955.) If you want to go faster than that, grab the 240 Weatherby Magnum or 243 WSSM for another 100 fps. If you want to go slightly slower, there’s the 6x47mm Lapua and even the 6mm Bench Rest Remington.
Why the 6mm Creedmoor?
Why all these 243-caliber (6mm) cartridges? Fine tuning. Truly. Any and all will suffice for taking game. It’s when you start tweaking performance in order to get a leg up on your competition that you justify these cartridges. And that’s why I’m probably not getting a 6mm Creedmoor. I’m not a competition shooter. I’ve already got a 243 Win. and a 6mm Rem. I use both for hunting and just a bit of fun target shooting. Both routinely group MOA, often half that with certain bullets and loads. Both match the ballistic performance of the 6mm Creedmoor. So the Creedmoor — balanced, accurate and mild shooting though it may be — offers me nothing I don’t already have.
This doesn’t mean it’s not perfect for YOU. It might not be radically different from our older 6mms, but it’s not the zombie shooter craze or today’s hula hoop either (that’s a 1950s reference, kids.)
If you’re in the market for a 6mm, you should seriously consider the 6mm Creedmoor. If you want to indulge in extreme range shooting and contests like PRS, especially with an AR-10 platform rifle, 6mm Creedmoor is probably perfect. If your need is for an accurate, flat shooting, mild-recoiling hunting rifle, a 243 Win. might be the smarter option because there are many, many more rifles and factory loads available for it. If you handload, either round will work just fine. As of this writing, only Ruger is producing factory rifles in 6mm Creedmoor, but that will surely change soon.
One More 6mm Creedmoor Consideration
Finally, here is one more consideration: rifling twist rate. This is critical if you appreciate long range potential and precision. As explained in this twist rate article, today’s most efficient, high B.C., long-range projectiles require faster twist rates than are traditional. Remington famously missed the boat with a too-slow twist rate (1:12) with its original 244 Remington cartridge in 1955. Forced to increase twist to compete with the 243 Win. (which you can read about here,) Remington reintroduced the 244 Rem. with a 1:9 twist barrel and renamed it the 6mm Remington as it’s known today. Unfortunately, too little too late, and this round is nearly obsolete. The 6mm Creedmoor may be the final nail in its coffin.
Most 243 Win. and 240 Wby. Mag. rifles come with 1:10 twists, which are not quite quick enough to stabilize today’s longest, highest B.C. bullets. Hornady recommends 1:9 twist or faster for its 105-grain A-Max and BTHP Match. Hornady’s new 108 ELD-Match needs a twist of 1:8. Hornady rates this projectile with a G1 B.C. of .536. Compare that to traditional 100-grain .243 bullets that top out with B.C. of around .405 and you’ll understand why the faster twist is needed. Other high B.C. bullets a 6mm shooter might consider are:
Berger 115-grain VLD Hunting (B.C. .568, 1:7 twist)
Sierra 107-grain MatchKing (B.C. .547, 1:8 twist)
Sierra 110-grain MatchKing (B.C. .617, 1:7 twist)
Nosler 107-grain Custom Competition (B.C. .525, 1:8 twist)
David Tubb DTAC 115-grain Closed Nose (B.C. .590, .620, 1:7 twist)
The writing is on the target board, folks. Shooters and the industry have finally tumbled to the inherent benefits of ballistic efficiency. Long range shooting and the need for aerodynamic efficiency are what’s driving innovation in new bullets and cartridges like the 6mm Creedmoor.
Conclusion
If you want a 6mm rifle of any kind primarily for hunting at reasonable ranges, a traditional 243 Win., 6mm Rem. or 240 Wby. Mag. will serve you perfectly. But, if you want to work with today’s most efficient bullets to minimize drop and drift while maximizing retained energy for downrange performance, you might want the new 6mm Creedmoor. It could well become the most popular 6mm cartridge of the future.
Ron Spomer doesn’t remember the year the 243 Winchester was introduced, but he was toddling around then. He doesn’t recall the introduction of the 6mm Creedmoor, either, because he was too busy shooting his 243 Winchester.
Very interesting and timely article. Just the other day on the range, a good friend was discussing the 244 Remington and how the 243 essentially killed it. It came up since I recently decided to run a 243 as my 6mm selection since I primarily shoot 600 yards and in.
I hadn’t ever heard of 244 until that conversion.
A 244 Remington was a 6mm with a 1 in 12 twist, I had one. It would only shoot up to 90 grain bullets.
All the .243 win needs is a faster twist barrel with a proper chamber cut and it is basically the same as the Creedmoor.
Yes, sir, and a 26 or 28 inch tube and you got a speed demon. If you really want to pop up the volume build a .243 Ackley Improved.
I love that 243 Ackley! But you’ve gotta get the fast twist barrel.
A barrel will burn out much quicker with a 243 the 6mm. Guys shooting PRS shoot. Lot of ammo, hence another reason to go to 6mm and 6.5s. I got a Desert Tech in 6.5 Creedmoor and haven’t touched any of my 308s since…
Baer45: I’m a bit confused by your comments. A 243 and a 6mm are both the same caliber, .243″. Are you meaning a specific cartridge? Please clarify.
I’m sure he’s referring to specific cartridges. The .243 Win and the 6mm Rem (used to be the .244 Rem before Rem retwisted the bore to 1:10 in 1963).
Al Chioffe, I’m not so sure about that. He might be referring to the 6mm Creedmoor, which the article was about. Regardless, the 243 Win shouldn’t erode barrels appreciably faster than either the 6mm Rem. or 6 Creedmoor. None are exactly overbored, although the more gently sloped shoulder of the 243 Win (20-degree) vs. the 30-degree of the Creedmoor MIGHT contribute to more eroding with sharp-edged stick powders. Thanks for your insights.
Thanks Ron, I have three 243 winchester and a 6mm remington. They all have there place in my gun safe. My family and I use them for just about everything. I reload everything I have so I reload both to the same velocity. It makes it easy for me. From a 55 grain bullet at 3800 FPS to a 95 grain at around 3000 FPS. Works for coyotes and deer. Don’t really need anything else.
Glad those little rifles are working well for you, Leslie. I’ve always found them deadly on deer. A bit much if you’re saving pelts on coyotes, but certainly effective at getting them! I knew a guy who fired 13 shots from his 243 to collect 13 6-pt bull elk over the years. It’s all about putting the bullet in the right spot.
Ron,
You refer to the .308 as the “great grandmother” of the 6 Creed, but the grand old .250 Savage of 1915 would be closer to the right answer for me. I have to believe one of its offspring,the .250 Savage AI, necked down to 6mm was the inspiration for the 6 Creed and necked up to 6.5 for the 6.5 Creed with the shoulder reduced to 30 degrees.
Mike, this discussion is about like the debate about how many angels can dance atop a pin. Given the head and body dimension of the Savage and its 1915 release — 9 years after the 30-06 and 12 after the 30-03 — I suspect Savage got his inspiration for the 250-3000 from the 30-06. And, given the current head and base body dimensions of the 6 Creedmoor match that of the 308 Win., I’m giving the nod to it. Honestly, the guys at Hornady used the 30 TC case to form the 6.5 Creedmoor, and the latter to make the 6 Creedmoor. However, you’ll note the head and body base dimensions of the 30 TC match the 308 Win., which matches the 30-06 which matches the 7x57mm Mauser which matches the 8×57 Mauser which is the oldest of the bunch, so that’s probably where it all started. Shortening, straightening case taper and changing shoulder angle is easy compared to making a significantly different head/base size. As for 6mm Creedmoor inspiration, my hunting partner John Snow at Outdoor Life reports here (http://www.outdoorlife.com/6mm-creedmoor-next-thing-in-long-range-shooting) that it came directly from the 6.5 Creedmoor. But your 250 Savage AI is a nice, efficient round. It was shoved into the background soon after the 6mm Rem. and 243 Win. hit the fields in the mid 1950s, and those sprang from the 7×57 Mauser via the 257 Robts. and 308 Win, respectively. Whew. Incestuous at best.
the 6 mm creedmore, is a new cartridge,? maybe not,,,,,,,, long ago there was a cartridge called the 6mm international,, in older sierra reloading manuals you can find it listed,,,,,,looks about the same as the 6 creedmore,,,,,,,nothing new really,,,,,
I really enjoyed that article. I own a .260, .308, .243, 6.5 Grendel, 6.5×55, and 6mm Rem. I was well on my way to build a 6 CM, and a 6.5 CM, but after reading your article, i think ill stick to my trusty old 6mm’s. I don’t intend to shoot over 500 yds or shoot long range competion.
Jeff, it sounds like you have that category covered!
Do you know what a donut is Ron? Do you know how accuracy is affected by dipping a long bullet into a case so you can put it in a mag or even chamber it? It’s not a water buffalo cartridge and is suitable for people who are recoil sensitive. Guess you have to load your own and shoot past 200 yards to get it. Sorry bud, you’re out of the loop on what we’ve learned about ammo and even your magazine recently hailed the 6.5creed and still didn’t touch on the perils of cramming a long bullet into brass multiple times.
The article on why the 6.5 creed (as well as 280ai, 300wsm, and 375r) is a modern marvel for folks that don’t wildcat and fireform and have time to remove donuts from their brass was a great read.
P.s. the 6 creed has been around a couple years now and being used by comp shooters that are winning. 6sir? Ever here of that? Why is it so good? Hmmmm
Sorry Ron, I think you missed the point and posting this really makes a person who knows some basics wonder.
*6slr
Chris, I’m sorry I’m not living up to your expectations. I do not pretend to be a world’s authority on every aspect of cartridge design, wildcatting, precision handloading and competition shooting. I understand there are authorities such as you on the cutting edge and I value your research and insights. Please feel free to share them with us. I am aware that John Snow arranged with Hornady to create the 6 Creedmoor from its 6.5 parent a couple of years back and I have heard that it is performing well in PSA competition. But, as a hunter, not a target shooter, I see no significant advantages in switching to it when I already have 243 Wins. and 6mm Rems. performing adequately for my needs. That was the gist of my article, not an in-depth treatise on precision handloading the 6mm CM. I trust that my readers can digest this information and disregard it if they need more detailed/advanced info.on the 6mm CM. By the way, are you seeing your donuts in cases with 40-degree shoulders more than 35-degrees or less? And how many resizings before they show up? And does the brand of brass play a significant role?
Sorry Ron, I think you’re a great writer and have read a ton of your articles in s.a.. All brass will donut after a couple firings with bullets crammed past the shoulder, which is inevitable with a long bullet with a 243 shoulder which is why all but a couple match shooters don’t use 243 as their go to. I still think the 243 is a wonderful round, and I appreciate its diversity above all else, it’s just apples and oranges and purposes.
I am extremely impressed by you posting my rant and appreciate your response. Thank you Ron, you are a a stand up guy.
You are welcome, Chris. As I noted earlier, I invite and appreciate input, information and new ideas from readers. Sharing is how we all help one another. I’m betting 99.9% of non-handloaders have never heard of interior donuts at shoulder/neck joints and probably 80% of handloaders never have. But now, thanks to you, a few more will. Thanks for the contribution.
I shoot a 8 twist bartelin barreled Rem 700 243. It is a hammer with a 105 gr amax. 24 moa up from a 100 yard zero puts it on at 1000 yards. That’s flat brother. as for barrel life, I’m into about 600 rounds so far and have seen no change in accuracy so I keep shooting it. When she gives up it will be another 243 chambered barrel on the action. The 6mm creedmoor is sexy looking! But it’s
just another way to throw a 6mm bullet.
Only 24 MOA at 1000 is indeed flat, Greg although 251 inches of drop is still pretty impressive, especially when you see that trace arcing in there. So you don’t feel the need to go with the Ackley version 243? I’ve often been tempted by that, but never taken the plunge. BTW, have you lengthened your M700 magazine box so you can seat those long bullets out farther or are you running a long action, or just seating deep as needed? How close can you get to your lands with that ogive? Finally, as if I haven’t asked enough ? already, what’s your MV? Thanks.
Another round for comparison is the 6mm-284. I have a rechambered Vanguard with a 1-10″ twist that shoots that cartridge. Just one of the 3 dozen or so rifles in my safe. I really enjoy shooting this little cheap coyote buster.
A few of you wrote of donuts when you shoot long bullets. I have never heard of them before this, I would like to know what they are. I have been reloading for about 40 years,buit i don’t shoot competion. I am curious. Thank you
Thomas, donuts build up as a result shortening cases to make a different cartridge. The worked/squeezed brass at the neck/shoulder junction “piles up” to create an internal ring. Firing and resizing cases can cause brass to accumulate at this “junction” too. This slight rim of brass isn’t a problem unless one seats a long bullet deep enough to engage it, which results in a tighter fit leading to increased pressures in a given load. If you load to peak pressures with no donut, then create one through multiple firings and resizings, there is potential for excessive pressure. Also for altering consistency in group size and location. You can ream out donuts, but the preferred technique seems to be squeezing them out with a mandrel and trimming the excess off externally. More experienced donut removers are welcome to elaborate.
Ron, these caliber/cartridge articles seem to create a lot of interest and controversy. Since I don’t handload or competition shoot, a lot of it does not seem to apply to me. I have centerfire rifles chamber for the 223, 243, 270, 308, 35 Remington, and 30-06. I hunt in Minnesota. In tight woods, my Marlin in 35 Remington is handy for deer. The 308, with better ballistics and higher energy, is also good in the Minnesota woods. I prefer it for black bear. However, my Browning rifle with a walnut stock that chambers the 308 is not nearly as handy or light as the Marlin. If I am going to be shooting across a field, say about 200 yards, then the 270 is a good choice. However, I would be able to hold dead on with the 308 and 30-06 as well. They are not quite as flat, but the difference is minor at 200 yards. Depending on how you sight in, you can stretch this out to 250 yards. I have not hunted Moose or brown bear yet. I hope to someday, and I think the 30-06 would be fine for them. My point is that I cannot justify another caliber, even when they demonstrate some ballistic superiority. Every time I add a caliber to the lineup, I have to stock the ammo and sight it in. There is also the question of ammo availability and flexibility. I can buy all but the 35 almost everywhere ammo is sold. All but the 35 come in various bullet weights and configurations. You can match the bullet to the game. I do understand the merits of various calibers for handloaders and competition shooters, but as a hunter do you see any need for me to add a caliber to my current lineup? Even if I plan a Western hunt, wouldn’t the 270 work? In an African plains game hunt, wouldn’t the 30-06 work? Thank you in advance for your thoughts on the subject.
You have it figured out, Louis. Your 270 Win, 308 Win and 30-06 can handle anything in N.A. and Africa. Just select the appropriate bullets for the tasks. Our multiples of cartridges are mostly to sell more guns and ammo and enable gun nuts to have fun. But don’t tell our spouses we don’t really need all these rifles.
Fortunately, after 49 years of marriage, my wife is enormously tolerant of my gun and fishing gear accumulation, which rivals a small sporting goods store. I am also tolerant of her online shopping and don’t ask what in all the boxes she orders. I just carry them in and say, “This box came for you dear.” By the way, I am an avid handgun enthusiast. Have you done any hunting with a handgun? I would love to see an article featuring handgun hunting if you are so inclined.
Hope to get to handgun hunting one of these days, Louise. Have done some and just got a new Kimber 10mm 1911 to work with.
I’ve shot 243 and 6mm all my life also there’s one point that everybody seems to be missing and if someone else mentioned this I’m sorry almost every 243 or 6mm that you buy off the factory Shelf has a rifle twist for a varmint bullet not for the heavy 100 – 115 grain 6mm bullets that we have available today, I have not brought or shot a factory 243 or 6mm that shot bullets heavier than a hundred grains in an acceptable way for me which leads me to speak up for the 6 Creedmoor I have a hunting rifle in 6 Creedmoor with a 8 twist barrel and I have varmint Target Barrel 6 grade that I’m fixing to break in my Snyder barreled lightweight 6 Creedmoor will put Copper Creek bullets in the same hole and I mean in the same hole I’m sorry I’m sticking with the Creedmoor I like the longer neck and I like the shoulder,, your 243 to me is not worth anything unless it has a new custom Barrel on it in an 8 twist or faster accuracy today is not what it was 20 or 30 years ago all of my rifles shoot in the teens forget that inch or less stuff I find a 6 Creedmoor easy to get to shoot, the factory 120 ELD match will shoot in the teens in my hunting rifle I can’t ask for much more
Good points about twist rate, Little Snake. You are right. If you want to shoot long range with extreme accuracy, the 6 Creedmoor should be your baby. I, however, am content to hunt my way inside 400 yards where MOA accuracy and 100-grain bullets fill my needs. Were I just starting my hunting/shooting career, I’d probably go with the 6 Creedmoor too.
Can i fire 6 rem through my 6mm creedmoor ruger percision rifle
No sir. The cartridge must fit the chamber and these two are not close in size or shape. They do fire the same caliber bullets, but that is all.