The 6.5 Grendel vs 223 / 5.56 debate – for ballistics, hunting or combat – is a LOT like a type of question I get at my day job. (I do gunsmithing and sales at a local gunstore)
I get asked all the time “which is better?”: 9mm vs 40 vs 45 ACP, 12 gauge vs. 20 gauge, pistol, shotgun or rifle for home defense, etc. The list goes on and on.
Whenever I’m asked those kinds of questions, I always reply with another question:
“What’s your purpose?”
This debate is no different.
Do you want to plink at the range? Hunt? Go into combat? If it’s combat, then combat at what range? Short? Long? Medium? All of the above? Are you preparing for when the “S” hits the fan? Do you want one “do everything” cartridge.
What’s your purpose?
Remember that Form Follows function.
If you just want cheap accurate ammo to plink at the range, forget any exotic cartridges (including the 6.5 Grendel) and just get yourself an accurate 223/5.56 rifle. PMC Bronze 55gr is well reviewed, accurate, consistent, and cheap.
FYI: If you buy after clicking most of the product links on this page, I'll make a few pennies out of each dollar you spend. It's not much, but it keeps the website going and I would appreciate your support. 🙂
You’ll spend a lot less money throwing lead downrange with a 223/5.56 than the 6.5 Grendel even if you reload.
I will add the caveat that if you are looking to shoot longer ranges, the higher Ballistic coefficient bullets of the Grendel will make shooting in the wind easier. But at 100 yards (or even 300 yards) in a light to moderate wind the 5.56 will be fine.
Maybe you want more than fine though.
Maybe you want extraordinary.
I’m the same way.
6.5 Grendel vs 223/556 Ballistics
Except for bullet drop, the 6.5 Grendel is ballistically superior to the .223/5.56 in every way.
Why?
Sectional Density is how “long and thin” versus “short and fat” a bullet is.
Obviously, longer and thinner bullets are more aerodynamic than short fat ones. Therefore, high sectional Density bullets have a higher Ballistic Coefficient (BC) than low sectional density bullets.
(Ballistic Coefficient (BC) is simply a measure of how aerodynamic a bullet is, with higher being better)
Some of the best 223/5.56 bullets have a BC around .400. However, 6.5 Grendel bullets are easily found in the .510 BC range, with many bullets being even better.
Because of the higher BC (i.e. more aerodynamic) 6.5mm bullets, the Grendel will drift less in the wind, lose velocity more slowly, and generally be easier to shoot accurately at long range and in the wind.
6.5mm bullets are famous for flying straight and penetrating deeply.
The 6.5 Grendel is no different.
6.5 Grendel vs 223/556 Terminal Performance
The 223 has a reputation for being both worthless and awesome in a fight. I wrote a whole article on Why 5.56 / .223 is BOTH the Best and Worst AR-15 Cartridge. It basically boils down to ammunition selection.
Pick good ammo, and the 223/556 is great.
Pick bad ammo, and the 223/556 sucks.
That same could be said of 6.5 Grendel or any other cartridge.
Shocking right?
For hunting or combat, the M855 “green tip” and FMJ ammo are both firmly in the sucks category (unless it’s constructed like the 7n6 bullet of the 5.45×39)
Many people ask me about “Knock Down Power” or “Stopping Power” in the gun shop. It makes me laugh (internally) because those terms have ZERO meaning.
No, seriously.
Can you measure “Stopping Power” or “Knock Down Power”?
How many more “Stopping Powers” or “Knock Down Powers” does a .308 have than a 5.56?
Terminal performance isn’t related to kinetic energy either.
Don’t believe me?
Then answer this:
The average football linebacker weighs 230 lbs and sprints at 25.5 FPS. That’s 2020 ft-lbs of energy. A 190gr bullet moving at 2200FPS produces almost identical energy.
Which is more likely to kill an Elk?
Not convinced?
A 490 grain Broad-head arrow traveling at 225 Feet Per Second (FPS) has a kinetic energy of 55 ft-lbs. A 1 Pound Gel filled bag launched at 60 FPS has a Kinetic Energy of 55 ft-lbs.
Same kinetic energy. One can kill deer deer, but the other would have trouble killing a squirrel.
Energy doesn’t matter.
I wrote a whole article on “Stopping Power” and The Simple Truth of Terminal Ballistics to explain how bullets actually do their damage.
Basically, the bullet must penetrate deep enough to reach the vital organs, and cause cavitation when it passes through them. A quality hollow point bullet will do that perfectly.
So…
6.5 Grendel vs 223/556 for Hunting
On smaller game it doesn’t matter.
No coyote in the world will know the difference between a 6.5 Grendel vs 223/556 hitting the boiler room (heart/lung area of the chest cavity)
But if you are talking deer sized game or larger, then a 223/556 is a little small. It absolutely can work, and there are people who hunt deer with a 223/556. The 223/556 CAN kill a deer.
But I would never hunt deer with a 223/556 for ethical reasons.
The bullet is too small/light (read: low sectional density) to ensure deep enough penetration and enough cavitation to quickly kill a deer. The deer might die right there, but it could also run a long way and dying a slow agonizing death.
You CAN do it, but that doesn’t mean you SHOULD do it.
I wouldn’t.
On the other hand, I think the 6.5 Grendel is the ideal size for deer sized game. (and good for larger game too.)
The 6.5mm bullets have excellent sectional density which translates to excellent penetration. Plus they have enough weight (momentum) to cause cavitation deep into the wound track. Exactly what you need for hunting, with the bonus of low recoil which really helps shot placement.
And NOTHING trumps shot placement.
You can’t miss fast enough to win a gunfight or fill a hunting tag.
Period.
I wouldn’t think about hunting deer until you can hit a 9″ paper plate Every Time at 100 yards from a standing position. That means you’ll hit the vitals at the average range a deer is taken. (40-50 yards)
If we’re talking 6.5 Grendel vs 223/5.56 on bigger game, then forget about the 223/5.56. I’m not saying it can’t be done. It can. But the margin of error is even less.
On the other hand, game up to Elk is within reach if you choose great ammo for for the 6.5 Grendel…
BUT
(and this is a big but)
You had better be a GREAT shot before you go after larger game. I don’t just mean with a 6.5 Grendel either. I mean with whatever rifle you’re using. Practice until you can hit everything you aim at with boring consistency.
*imitates Yoda’s voice* Then, and only then, a Jedi will you be.
Thanks to the high sectional densities of the 6.5mm Bullets, you can take game that is quite large with the “lowly” 6.5 Grendel. Part of that is thanks to modern bullet technology…
…But you have to put those bullets in the right spot.
I don’t care if you’re using a 6.5 Grendel, 223/556, 308 Winchester, 338 Win Mag, or a fire-breathing .500 Shock & Awe Magnum.
You can’t miss fast enough to win a gunfight or fill a hunting tag.
Period.
Firepower is no substitute for accuracy and it never will be.
Don’t pretend it is.
The 6.5 Grendel is a very capable little cartridge, but it has it’s limits. Yes the Grendel can take Elk at 400 yards as Mark Larue proved. But Mr. Larue is a good hunter and a great shot.
Most of us aren’t.
For Deer, the 6.5 Grendel is about perfect, and in normal hunting ranges, (40-50 yards) makes an excellent deerslayer. The 223/5.56, is a little too light in my book. It can be done, but I wouldn’t try it.
6.5 Grendel vs 223/556 for Combat
I LOVE the idea of a General Purpose Combat Cartridge. A single cartridge which is effective over the entire range of distances a soldier could engage an enemy is the ultimate in versatility.
And I LOVE versatile equipment.
But the biggest downside of versatile equipment is it loses to specialized equipment when you’re in the specialized equipment’s field.
The 5.56 was designed for Close Quarters Battles(CQB). From the ground up, it was designed to be highly lethal at close range. It’s low recoil and high lethality (with good ammo) make the 223/5.56 almost perfect as a close range combat round…
…Almost
223/5.56 has one glaring flaw: Barrier penetration.
With good ammo, it’s MUCH less of a problem. However, the relatively lightweight 223/5.56 bullets have very low sectional densities which result in relatively poor performance when faced with barriers.
Unfortunately, barriers are a fact of combat.
Enemy soldiers take cover. It happens.
When they do, you have two options: either shoot through the cover or wait for them to come out from behind the cover.
(or call in an air/artillery strike. That works too.)
With good ammo, I would be very happy with 223/5.56 in close quarters, and even out to ~200 yards
However, one problem that’s not solved by better ammo is deflection when shoot through glass.
In Iraq and Afghanistan, one tactic the bad guys used was driving cars or trucks with explosives into US checkpoints. The easy way to stop the truck is shoot the driver, but the 5.56 bullets tended to travel in odd directions after penetrating the glass. Often, it takes many repeated shots to hit the driver shooting through the windshield.
Heavier bullets have this problem much less.
By contrast, the 6.5 Grendel was designed from the ground up as a hunting cartridge that would extend the effective range of an AR-15.
If you’ve read my General Purpose Combat Cartridge article, You’ll know that the 6.5 Grendel only falls a little short of being an ideal one-size-fits-all military cartridge. (partially based on based on military testing, see the article for details)
But the 6.5 Grendel does fall short.
The bullet weight/diameter is right, but the velocity is just too low.
However, it does have a much longer effective range than any other AR-15 cartridge. (yes, slightly longer than the 6.8 SPC, details in my 6.5 Grendel vs 6.8 SPC article.)
The Grendel has double the recoil and slightly less capacity than the 223/5.56. The 223/5.56 has issues at longer ranges and through barriers.
If I knew I would only be shooting at relatively close range (0-200 yards) and I knew barrier penetration wouldn’t be an issue, I’d take a 223/5.56 over the Grendel in a heartbeat.
But I can’t know that.
In fact, the opposite is likely to be true.
Enemy soldiers take cover, windshields are a fact of life, and half the engagements in Afghanistan took place at over 300 yards.
As far as 6.5 Grendel vs 223/5.56 goes, I prefer a more versatile cartridge than can handle varied threats. The 6.5 Grendel isn’t an ideal General Purpose Combat Cartridge, but it’s better than the 223/5.56.
It has a longer effective range, can punch through barriers better (thanks to it’s higher sectional density and momentum) has a higher hit probability at long range thanks it’s better wind resistance, and a longer effective range thanks to heavier, more aerodynamic bullets.
Conclusion & Misc
The 6.5 Grendel is an Excellent Jack of all trades cartridge….
But it’s not perfect.
223/5.56 is cheaper to shoot, the cheap ammo is more accurate, and has half the recoil. 6.5 Grendel is better at target shooting, hunting, and combat, though more expensive to shoot.
The cheap 6.5 Grendel ammo is the Wolf 100gr steel case. The price is amazing at only $0.28/round. ($5.60 for a 20 round box. 223 steel case ammo is slightly less at ~$0.24/round or $4.80 for a 20 round box)
Plus, the cheap Wolf 100gr is constructed like the deadly 7N6 bullet used by the Russian military’s 5.45×39.
Pinched from a forum post by David Fortier, all credit for the photo goes to him.
See the hollow cavity in the front? When the bullet hits something that cavity collapses and makes the bullet flip and spin around in all sorts of nasty ways. It creates a very messy wound track and causes all kinds damage.
It works so well for the Russian 5.45×39, that it’s earned the nickname “poison pill” because it’s so small yet does so much damage.
Yeah, it’s pretty awesome and available for as little as $7/box as I write this in February of 2016.
In virtually every way you compare performance, the 6.5 Grendel vs 223/5.56 is a no contest, no brainer. However, the 223/5.56 is cheaper to shoot, and the cheap ammo is more accurate (and thus more fun) to shoot at the range.
The 223/5.56 is also arguably better for shooting varmints because the trajectory is flatter over the first few hundred yards.
It doesn’t have to be one or the other.
My solution to the 6.5 Grendel vs 223/5.56 debate is simple: Get both. AR-15 uppers aren’t hard to swap or too expensive. You can shoot and practice for cheap with 223/5.56 ammo, and you always have something a little bigger in your stable for hunting or longer range target shooting.
Will a little heaver recoil spring lessen the felt recoil of the 6.5 Grendel?
Yes and no. Let me explain: there are four phases of recoil in a semi-auto rifle.
#1 is the bullet pushing off of the gun/you. all guns do this, even bolt guns. the rest are only applicable to semi-auto weapons.
#2 is the gas system pushing the bolt to the rear, which actually pushes the gun forward, slightly reducing felt recoil.
#3 is when the bolt (or buffer weight in an AR-15) “bottoms out” and slams into the rear of the receiver/buffer tube, slightly increasing felt recoil.
#4 is when the bolt slams home, slightly reducing felt recoil.
A heavier spring can reduce #3 if the bolt stops under spring pressure alone and doesn’t slam into the rear of the buffer tube. The difference in recoil is there, but it’s not huge. However, a stronger spring can also create cycling issues if the spring is too strong.
Instead, I would recommend (and have on my personal AR) a high quality Adjustable Gas Block. It allows you to tune the rifle almost no matter the spring strength. It can also completely eliminate the #3 phase of recoil because the bolt won’t slam into the rifle.
Hi love the articles, first time responder, have both a comment and. A question simultaneously,concerning the knock down power thing? : ok: the scenario your in a long firefight it has degraded to knives and side arms close in fighting your swinging and plinking with bayonet and your side arm, suddenly a guy from atop a slightly elevated. Burm is bearing down on you with his battle rifle bayonet fixed rushing at you, you’ve got time for one maybe two shots, you have the choice of a 9mm or the ole 45, what do you choose? The 9mm is weak and will throw some holes in him but he will still plunge his bayonet into you, the 45 now that will knock him back on his ass the moment that pumpkin chunker starts hitting him you’ll get a few more rounds on him because he’s thrown back and devastated by the kinetics of the round, at the very least to the side guts mutilated bruised and dead, at that very moment you’ll understand KNOCK DOWN POWER! That’s first hand information,of course deer don’t attack with bayonets but that charging full grown boar? I’ll take the knock down punch of certain weapons all day, 50 Beowulf you know etc,etc,like you said what’s the purpose? I liked your analogy though it was good,truth is 9mm weak clean holes much ,much less tissue devastation.45 very large tissue devastation, heard a guy shot with one in the torso say felt like the hulk punched him in the chest, knock down power,a great description of the opposite argument though,don’t you think?
If you read my 9mm vs 40 vs 45 article, there’s a link in that article to a story about cop who put 14 rounds of .45 ACP hollow points into a bad guy, and the bad guy “wasn’t even close to slowing down.”
The problem with “Knock down power” is that it’s proved wrong by the laws of physics. Newton’s third law states “For every action, there is an equal and opposite reaction“. That means all of the “knock down power” the Bad guy feels, you also feel in recoil when you fire the gun. If your .45 bullet would knock the bad guy down, it would knock you down too.
For more technical reading, I suggest the FBI report Handgun Wounding Factors and Effectiveness, and also the FBI’s justification for going back to 9mm. The first one will also explain the psychological reasons why some people are stopped (even “knocked down”) by a 22LR and others aren’t with a .45 ACP.
In the scenario you suggested, I would rather have a rifle because pistols just don’t stop people very well. If I had to choose a pistol, I would take my 9mm CCW because It’s what I’ve trained with the most. At that range you’d need to hit the spinal cord or brain to stop him in time (with a pistol). I cover most of this in my article on terminal performance, and it’s also mentioned in my 9mm vs 40 vs 45 article.
Abe: Sweet article about my favorite bullet for deer hunting. The ole 6.5. I hunt with a old 6.5 x 55 Swede with a 29″ tube. I bought it mail order for $100 buck along with 500 rounds of Milsurp SWEDE loads for an extra 50. I get LOTS O LAUGHS at the deer camp, until she drops my venison at 250 clicks. Yes,,,Yes…Yes. She is scoped mounted as I am 65 plus and ‘shake’ and eyes are going due to cataracts but…but…but…gimme my old SWEDE avec the LEUPOLD and my Barnes 140 Grain X bullets atop my home cooked hot hand loads and let me and my SWEDE do our thing. (My old Carl Gustav eats the all!) The BC issue is very POIGNANT! In the 6.5 calibre, one must go the the 30 calibre in a 180 grain bullet to match the 6.5 at 140 grain. 6.5-140 grain BC = .498. Gotta love it!
Something I think you completely glossed over is that the M855A1, which has been standard issue for several years performs really well out of 14.5 inch to 22 inch barrel weapons, while there is limited data for these other rounds out of short barrels.
Also being heavier doesn’t mean it will go through a barrier, because vests and proven to have .308 and 7.62x51mm bounce off them, completely fail when fired with green-tip ammo.
I have seen this happen over and over again. The vest is rated to stop military spec 7.62x51mm and then it fails when shot with green-tip. They get it to stop .308 rounds, which are stronger then 7.62x51mm mind you, but then the ammo with hardened steel in it blows a hole in it.
On top of that, vests that stop .44 Magnum have been shown to fail when shot with Russian 9×19 +P or good 7.62x25mm.
When considering military ammo we also need to consider if the round will tumble inside of people, which I know longer bullets are more capable of doing. The question that no one seems to be asking is “If the M855A1 is steel in the front and copper in the back, how long does a round need to be to compare to the level of instability that bullet will have inside a person”?
Every time 5.56 had any problems, it just gets updated to fix them, which is what America does. This reflects how we are on our fourth or fifth DU 120mm sabot, why change ammo when the old stuff is perfectly good if you make it a little heavier or faster?
I’d right an entirely new post on how stopping power does matter but I will simply explain to you a little bit of physics. Kinetic energy is the amount of energy which something holds. KE=Weight*Velocity^2, this may seem like something meaningless to you beyond “Which is more likely to kill an Elk?”, however, if you had ANY idea beyond that you would understand the importance of normal force in, as you say, “[Killing] an Elk?”. The only thing that makes a bullet so effective is the fact that it has a small area, meaning, on impact the target has a much smaller amount of space to apply a normal force. The target then is FORCED to exert the SAME AMOUNT of energy to stop the bullet. The wider the bullet the less effective. Making a bullet ever so slightly larger increases the radius of the bullet making it ever so less effective, even if it has the same amount of energy. Momentum (weight*speed) is what you are referring to as the damage, which makes sense mostly. The only reason stopping power matters? Well, the way plate carriers work, they disperse the energy of a bullet over a wider area, like one’s chest. Would you rather take 9mm or 45acp to your plate carrier? I mean I’m sure you’d say the 45acp because they’re such similar rounds. Id rather be shot 10 times with 9mm in a plate carrier that 3 with 45acp. The fact that 45acp has double the STOPPING POWER as 9mm, means you will have to excerpt more energy to stop it, more damage in the same spot causes more damage, as i say, meaning the .45 would in turn, be more effective in combat due to the fact it can be shot a bullet proof vest and actually hurt. Learn more before posting stuff on something you have no idea about 🙂 “Which is more likely to kill an Elk?”
Mention my grammar and you’d just be asking to lose another argument.
First, Kinetic Energy is actually computed using KE=1/2(MV^2). Please check if you don’t believe me.
Second, If you had read my Article on Stopping power and terminal performance you would’ve noticed this excerpt: “Energy is NOT a good indicator of a bullet’s lethality. Energy is simply the ability to do work. Nothing more, nothing less. It’s HOW that work is applied that determines how lethal a bullet is.”
My point is merely that “stopping power” is meaningless term because it is not quantifiable.
Also, I would like to see some scientific claims that prove .45 ACP has “double the stopping power as 9mm.” If you’ve read the FBI’s rational for switching back to 9mm you’ll realize the FBI disagrees. I also have hard statistical data in my 9mm vs 40 S&W vs 45 ACP article that indicates otherwise.
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I have read and understand all that you wrote. I agree with you on skill and shot placement. Practice until your friends are bored looking at your targets. I started using a Colt Elite ( switched out the 1:9 for 1:7) 25 years ago on white tail. When no one was thinking of hunting with AR’s. I was even ridiculed by some hunting friends. Never missed, one shot kills, 25% dropped the rest went the usual 30-50 yds. I wouldn’t advise anyone to do it. Discipline is important, in practice and weather to shoot or NOT shoot. You should see what a 64 gr pp does to the heart and lungs.
No argument on anything you say, except, normal deer hunting range is 40-50yards, I could hit a deer in the eye with 5.56 at that distance, brain kill at that range. In normal hunting range here in Wyo I fully agree with you on 6.5.
Thank for all the great complete articles
Thanks for attaching references to your articles.
Why so casual about killing innocent animals? Don’t tell me you need to because there would be too many if you didnt. I’m all for people having their guns but leave the defenseless alone. They don’t deserve that end. Self defense yes, murder for recreation..no. You don’t need them for food. No, some stupid god did not put them here for you to use or abuse. Thanks for the info about calibers and performance ballistics. Much appreciated.
I love hunting dear and I love venison. Hunters treat wild game animals better than any cattle butchering operation.
Hunters only shoot at guilty animals.
If hunters weren’t hunting deer, farmers would be poisoning them. Deer are extremely expensive pests. The only reason farmers put up with them is because they can hunt them. Based on your post, you must be a vegan. Anything less would involve you killing defenseless animals from a concentration camp.
I don’t think the author was casual about shooting deer. This was simply a comparison simple and sweet. The over population theory is a fact as many natural predators have been eliminated due to our thirst for beef other meat. I have not killed a deer yet but have no reason to fault others who do. I fish and kill plenty with a blunt object after bringing aboard. It is quick and as humane as possible. Funny that animals hunting animals do not abide by our ” standard” for clean humane kills. By the way I love venison and get it regularly through friends that hunt. We are part of the food chain whether you like it not. Good day.
Hi . after nearly one jear I managed to get a 6,5 Grendel in an AR with a 20″ bull Barrel Lauf Lothar Walter. In Germany this is a really rare caliber for an AR. So I apologise if I may disturb you, but I want to ask you guys, if anybody got experience about amunition with this Caliber for shooting 100 Meter with the best accuracy.
Most people report exceptional accuracy with off-the-shelf Hornady 123 grain AMAX ammo. I would start there for accuracy.
6.5 Grendel has equivalent ballistic performance to that of .308 at distances out to 350 yards. I have significant experience with the round through my AR-15 lower with a 6.5 Grendel bull barrel upper (actually manufactured by Mossberg). There’s very little felt recoil difference between the 6.5 and my 5.56 upper, so it’s an excellent hunting round for my wife and for my 14 year old son. He was hunting with a .243 before I acquired the Grendel upper, and very much prefers the Grendel. His shot groups definitely back this up, as do my wife’s. All in all an excellent round. The only downside is somewhat limited availability of ammunition. I’ve had pretty good luck with Hornady Black 123 grain match. Again, its ballistic performance is on par with.308 with significantly less recoil, and is superior to the old standby 30-30. So for deer, feral pigs, coyotes etc. it’s a great little round.
I just simply wish to know that max effective range of the 6.5 Grendel
Unfortunately, the answer to that isn’t as simple as it appears.
If you mean for hunting purposes, then you need to find the minimum expansion threshold of the bullet you’re using. Then calculate at what range the bullet hits that velocity and you have maximum effective range. However, because different bullet weights and bullet types have different velocities, expansion thresholds and Ballistic coefficients, the answer isn’t simple. It’s easy to calculate with the right information, but it’s not as simple as XYZ range.
That said, almost all Grendel loads are good to 300 yards for hunting purposes. If memory serves, some are still at/around the expansion threshold at almost 500 yards. For ethical hunting, you’d need to know the limits of your bullet. (and your accuracy)
The same rules apply in a combat role, but people are more fragile than deer. If you put a bullet through the heart/lung area or head, your target will go down. Our special forces have made one-shot kills at 700 yards with a 5.56, so a Grendel could go at least that far (for combat).
I think the real question is “how good of a shot are you?”
Awesome article, thanks so much. I’ve been debating 6.8 special vs 5.6 Grendel for a while. I reload a lot so keeps cost down and 6.5 bullets are relatively easy to find.
What’s your take on 6mm Creedmor?
I love the 6.5 Creedmore, but the 6mm Creedmore is getting close to overbore. In my how to compare cartridges article I mentioned that once you have a heavy-for-caliber bullet going ~2800 fps, more velocity starts burning barrels out pretty quickly. There’s a whole host of 6mm cartridges (.243 Win, .243 AI, 6×47 Lapua, 6mm Remington, etc) That get over 3000fps with 105-108gr handloads and the 6mm Creedmore is about the same. I’m not sure what the 6mm Creedmore does that those cartridges don’t.
If you like really fast 6mm bullets, you should be very happy with it.
I would say inherent ease of finding a accurate load. The cartridge is not picky. The rifles chambered in 6mm Creedmoor also have a faster twist off the shelf if, like most folks I would wager. Such as a Ruger Predator. This allows it to effectively stabilize the longer projectiles much easier. The 243 has a standard twist of 1 x 9.25 or so in modern rifles and this allows ease of stabilization around the 95 gr area with normal velocities. The 6mm Remington was developed for even lighter grain projectiles around the 65-70 gr area if memory serves. Its standard twist is somewhere around 1 x 10. At the end of the day its all in what your purpose of your rifle is unless you want to spend more money on a custom barrel with different twist rates. I know personally the 6.5 Creedmoor is very easy and forgiving to find an accurate load due to several different aspects of the cartridges design. The .243 isn’t near as easy to load for heavy for caliber bullets. As to the why the 6mm Creedmoor and other similar speed cartridges are becoming more and more popular I will give you two or three reasons that I have come across. First, flight time to the target is less and therefore less time for wind to affect the projectile. 6 mm projectiles have come a long way. The newer 108 gr Hornady eld match projectile sports a .542 bc I think. The 6.5mm 143 gr is around .631 bc. That seems significant but due to the faster flight time it becomes a rather small difference. The second reason is less felt recoil which means faster follow up shots and time to see the bullet impact on target at distance. Finally for some, its just a tad cheaper to do near the exact same thing. Abe is right about it being overbore. However, most people will not shoot a rifle enough to out shoot the barrel. Just my 2 cents. Nice article Abe.
Sorry cut myself off a sentence earlier on.
Most folks don’t have money to spend on custom rifles or barrels vs buying a rifle of the shelf.
Thanks for writing that. 🙂
Love your style and the verifiable info you produce. Thanks for your time and effort.
So do I just have to swap my barrel out to 6.5 and get a different clip? Or is there other modifications needed to build a 6.5 from a standard AR15 platform?
You’ll need to change the barrel, bolt and magazines. Also, 223/5.56 muzzle devices are too small for the 6.5 Grendel. I have a complete parts list for 223/5.56 AR-15, and it includes substitutions to turn it into a 6.5 Grendel. Just put your email address into the form on the page and It’ll get emailed to you.
Hi,
Came upon the site via google, after reading my country’s army is experimenting with 6.5 Grendel, after decades of Kalasnikov 7.62 rifles and ammo.
Great info with lots of common sense and experience. Bookmarked!
Loved the posts explaining stopping power and “hydrostatic shock”. 🙂
Cheers from Serbia
Dear Abe,
Great site/info.
I am thinking of rebuilding my HK MR 223 (think in the US it is denominated 556) into 6.5 Grendel for Service Rifle Comppetition only.
Please kindly email me your recommendation of parts required for such AR15 rebuild into 6.5 Grendel.appreciate!
Tks and rgds,
Piotr
my AR-15 build guide has a 6.5 Grendel parts list. You’ll need the barrel (which comes with a Grendel bolt) and magazines. Also, a muzzle device is a good idea. you also might need a new gas tube depending on your current gas system length.
Bear Creek Arsenal, Sanders Armory, Brownell’s and several others sell complete 6.5 Grendel uppers for the AR platform. They include the bolt carrier, charging handle, barrel, hand guard, flash suppressor, gas block, etc. All you have to add is your choice of optics and buy some magazines. They advertise that the 5.56 magazines will work, but that’s not entirely true. If you try to stuff more than 5 or 6 rounds of Grendel in a 5.56 magazine, the magazine swells up and doesn’t feed into the mag well. So go ahead and spring for the extra $12 per magazine and save yourself the aggravation.
if a coyote cant tell the diff between a 6.5 and 223/556 then wouldnt a person not be able to tell the diff? I think the 556 has enough stopping power for war, people are trying to ban the ar556 from civilian use because it showed devestating outcomes in the wrong persons hands. the 6.5 is better but barrel life makes it a prob in warefare, also the barrel on a 6.5 would have to be longer for it to even make a diff in ballistics, which means more weight. i think a heavier 223/556 would be a cheaper better solution. i hunt with 75grain 223 hollow points and it knocks hogs down hard.