6.5 Grendel vs. 6.8 SPC vs. .308

I have been looking at these calibers for several years now.  I have read most everything I could get my hands on to help me figure out what would be the best “all-around” AR-15 caliber.  I should specify when I say “all-around” I am considering:  hunting (varmint to deer size), long range target and hunting, CQC or self-defense, cost per round, accuracy, penetration and “knock-down” power or ft-lbs of energy delivered.  

I have read so many articles and there seems to be more “emotion” and “personal taste” than facts and ballistics.  My goal here is to present what I was looking for several years ago before spending money on AR uppers.  I have 5 different calibers of ARs and love most all of them (see my review of the 450 bushmaster) but I was looking for “one” several years ago and I know many people that are looking for just one upper to meet their many needs.  Many people even consider some of the AR-15 calibers against an AR-10 (.308).  I have compared many different manufactures of these three rounds with various bullet weights.  They have all been fairly consistent.  I chose to use Hornady for this comparison just because of their reputation and my experience with them.  The ballistics I took from Nikon’s “Spot-On Ballistics Match Technology”.  I also looked at Hornady’s ballistics however they only had info going out to 500 yrds.  It still remained consistent with other info I have seen.  I always say “the proof is in the pudding”.  Take a look at the ballistics and look at the ballistic co-efficient (BC) for each of them.

6.8 SPC 120 gr Hornady SST (found as low as $.86 per rd for Hornady and cheapest (Remington) at $.79 per/rd)
Test Barrel (16") Velocity (fps) / Energy (ft-lbs)
MUZZLE100 200 300 400 500
2460/1612 2250/1349 2050/1120 1862/923 1685/756 1522/617

6.5 Grendel 123 gr Hornady A-max (found as low as $.88 per rd for Hornady and cheapest (WolfGold) for $.62 per/rd)
Rifle (16" Barrel) Velocity (fps) / Energy (ft-lbs)
MUZZLE100 200 300 400 500
2350/1508 2189/1308 2034/1129 1885/971 1744/831 1612/709


.308 155 gr A-max (found as low as $1.04 per/rd for Hornady)
Test Barrel (24") Velocity (fps) / Energy (ft-lbs)
MUZZLE100 200 300 400 500
2850/2795 2639/2397 2438/2045 2245/1735 2062/1463 1887/1225

I would have to say it’s a “no-brainer”.  The 6.5 Grendel will outperform the 6.8 SPC in most every way.  I have read arguments that the 6.8 SPC is a better CQC rd.  This just kills me when I read “the 6.8 will outperform the 6.5 under 300 yards” “go with the 6.5 for long range hunting and the 6.8 for more knock down power”.  REALLY…..Why?..........  Kinetic energy is almost EXACTLY the same from muzzle to around 300 yards with the same wt bullet.  The difference is so small it is irrelevant.  It would seem that there is little difference regarding accuracy at these distances as well (most would agree that the 6.5 always has a slight advantage for accuracy due to BC at any range).  However, after 300 yards the 6.5 really takes the lead and the same goes for speed and accuracy.  So 0-300 yards they are relatively equal.  Look at 500-1000 yard distance and there is no comparison.   Why would you not want to have both short and long-range capabilities?  In fact, if you compare the 1000 yard ballistics of the 6.5 Grendel with the .308 it is shocking just how close the two are.  The 6.5 is slightly faster but slightly less energy due to the lighter bullet.  The sectional density is very impressive for the 6.5 so the penetration is most likely better than the .308.  I am only making the comparison between a 6.5 to a .308 at “long” distance.  There is little comparison regarding speed and energy less than 500 yards.  Under 500 yards the .308 is far superior in both.

I have also heard that the 6.8 outperforms the 6.5 with shorter barrel lengths.  Go to Hornady and compare the 6.8 SPC 120 gr SST vs. the 6.5 Grendel 123 gr A-max.  The 0-500 yard ballistics for both are out of a 16” barrel and are very, very close out to 300 yards where the 6.5 takes the lead in both speed and energy.
What about cost?  I have read many articles that supported the 6.8 over the 6.5 due to cost per/rd.  The 6.8 has more companies that produce the cartridge however the cost per/rd can be found cheaper for the 6.5 (checkout ammoseek.com).  I purchased 500 rds of WolfGold MPT for $12.50 box/20 rds.  That is pretty cheap!  Word is that Wolf is going to start producing steel cased ammo in 6.5.  With the recent release of the “6.5 Grendel” trademark from AA, it is only a matter of time before more companies cash in on this caliber that has been “not so attractive” due to royalties in the past.   Currently, I have only found ammo for the 6.5 in 2-3 different manufactures.  My hope is that this will change as more people realize the capabilities and reality of this caliber.  The cost per/rd from Hornady is about the same.  Both are much cheaper than match ammo in the .308.

If you are into re-loading, the 6.5 has a very large selection.  Hornady has 14 different selections ranging from 95 gr to 160 gr.  The 6.8 also has 14 to select from based on .277 or 270.  They both have a good selection for re-loading but currently the 6.8 SPC does enjoy the advantage in the variety of ammo available.
If I had to choose one of the three for everything from: CQC, combat/self-defense, hunting, target shooting at both short and long range, weight of ammunition and rifle, and cost for shooting……….. The 6.5 Grendel wins without a second thought.

I could not figure out why the 6.5 had not been adopted by the military and more embraced by the civilian population for years.  Many wanted you to believe it was the lesser of the two cartridges.  There were problems with the legal aspects related to name/trademark “6.5 Grendel”.  It was a trademark/legal/royalties issue that kept a great cartridge from being produced by most of the mainstream AR companies.  The GOOD news is that the 6.5 Grendel has been accepted by SAAMI and that Alexander Arms has agreed to release their trademark on the name "6.5mm Grendel".  We should see in the next year a MAJOR growth of companies producing both weapons and ammo in the 6.5.  I seriously hope the military will now take a second look at this cartridge for NATO.  The history of the 6.5 is as long as it is impressive.

BOTTOM LINE………..do the research (should not take long) and see for yourself.  This is a SUPERIOR cartridge for hunting (vermin to medium to large game), short and long distance target shooting, low recoil for younger shooters or faster follow up shots, and cost effective for shooting.  If you are limited on “coin” and need to pick one upper to do it all, this is the one.

Your going to hunt deer with an A-Max?

And your comparing SAAMI specs BTW. Not spec II on the 6.8.

Your post is a little long, but it reflects the due consideration that these calibers deserve.
If you haven't seen it, this long read is very worthwhile.  Through all of the developments, a

viable point it made for the 6.5, at the end of the whole body of research and testing.  It's

very interesting to see how many attempts were made that came close enough to being

optimum, but got passed over for whatever reason.  This article suggests that the current

reason why NATO isn't looking for a replacement for the 5.56 and 7.62 is because the day of

the brass cartridge case is nearing its' end.
http://www.quarry.nildram.co.uk/Assault.htm
It's very interesting as well to read over the forums for both the 6.8 and 6.5.  On the6.8 forums,  the general consensus pretty much sticks with the idea of an "assault rifle" caliber to

be applicable within 300 yards.  On the 6.5 forums, we see a lot more mention of the 6.5

being viable to more like 800 yards.
To me, all of this discussion is difficult to put into perspective.  If the only consideration was

a civilian sporting round that best serves to thin out the herd in the gunsafe, these new

rounds would have a lot more merit.  In this world though, it's pretty clear that we're headed

into a whole lot more terrible conflict where Joe Civilian is better advised to stick with current

NATO calibers.

Why not use A-MAX?  The last thing you want is a round leaving your target.  ENERGY LOST.  Especially with smaller rounds.  Why do you think the Geneva Convention made HP illegal?  The goal is not to “kill” the enemy, it’s to “wound” them and HP (or rapid expanding) delivers more energy into the target thus being far more fatal wounds.  I always use HP in my 5.56 and have had great luck hunting deer.  The only reason I have not used the A-max is weight.  I want a heaver bullet for my 5.56.  To answer your question, “YES”, I plan on using my A-Max for hunting in my 6.5 so as to deliver ALL the kinetic energy into the target and not the trees on the other side.  The sectional density of the 6.5 provides outstanding penetration which is great at distance but not for a deer at 100 yrds.  I spent 13 years in the medical profession both civilian and military and if you do a little research on gunshot wounds you do not want over penetration if your intent is to “kill” your target.  This is why in most states FMJ ammo is illegal for hunting.  Snipers use HP.

I guess I'm reading it differently than you (not sure how that is) but given the stats you've listed, the .308 at 500 yards is still 17% faster than the 6.5 (with a bullet weighing 26% more) and has 173% the energy of the 6.5.

Also there is plenty of 147 to 150 grain .308 ammo available for less than $0.60/round, some of it boxer primed and so reloadable, although the really accurate stuff like Federal GMM with 168 gr SMKs averages over $1/round.

That said, I don't consider 7.62x51/.308 a do it all round as (for me anyway) the recovery between shots is longer than I'd like for closer encounters.

6.8 SPC and 6.5 Grendel do come much closer to satisfying that requirement.

Dunno where .300 AAC compares but I suspect it's a little weaker than the 6.x variants as I've heard it compared closely to 7.62x39...

Joe

You are completely right.  It is compairing apples to bananas however at 1000 yrds they are VERY similar.  It would be nice to have something that fits on the AR-15 that could come "close" to a AR-10 in range and energy.  That was the point I was trying to make.  I may have done a bad job in making that clear.

I'm just saying with the availability of the Hornady 6.5  129 SST you gain a purpose made hunting bullet and don't loose too much BC.
Hit a shoulder with that A-Max and track your kill ... or put an SST through it and watch it fall right there.

Do you have any stats for the 6.5 Grendel with a barrel longer than 16 inches?  It's hard to compare a 6.5 out of a 16 inch barrel to a 308 out of a 24 inch barrel.  Some calibers act more favorably with longer barrel lengths than others.  For instance, there's a decent velocity gain with 5.56 going from 16 inches to 20 inches.  I think that the Grendel is the same way.  I'll bet the Grendel will come a little closer to 308 energy delivered out of a 20 inch or 24 inch barrel.

the geneva convention didnt.

OP, you are ignoring the elephant in the room.
Specifically, the SSA 6.8 140gr VLD.

Nick

Dear Professor,

Please cite the place in the Geneva Convention that made "HP" ammo illegal.

Thanks,
FB

Oh, to stay on topic, I like the 6.5G. in the AR15 sized platform.

HP ammo works very well from the barrels of our fine snipers and has for years.  SMKs are in the fight every day.

Great article you referenced when you get to the bottom and see the ballistics chart.  Looks like the only negative to the 6.5 Grendel is that the military may have to give up a little juice in order to use longer, non-lead penetrator type bullets to satisfy NATO.  It seems to surpass the 7.62x51 at 500 meters in energy delivered while still being very acceptable up to that point with less recoil. On paper, it seems superior to the 6.8 (spec I at least) and obviously superior to the 5.56.

Topic Moved

Grendal does it all, but isn't the best at anything....

6.8 is the best in sbr,  even 308 doesn't offer tons of advantage to it in terms of energy
and when you consider the weight, loss of capacity and recoil/follow up shots
I am inclinded to say 6.8 wins

16in 308 wins, good velocities and able to make it to 1k, and much more aval. ammo than the other two
and better at barriers

grendal awesome bc, light recoil

just my view

I like 6.8 cqb sbr 12in
over 100m 308  16in

None of them are the best at all roles, ea has their ninche and significant advantages over the other

I guess you have to decide what length of bbl you want, or role to fill before deciding,

Hell even the 5.56 can beat these at one thing
speed at which one is able to suppress targets

I totally agree but the only match ammo I have been able to find from Hornady is the A-Max.  I dont reload so my options are limited.  5.56 A-Max hitting the shoulder I agree but the 6.5 A-Max hitting the shoulder I feel very confident it would punch through and drop it.

I really tired to find consistent compairison data, even tried contacting Hornady but did not hear back.  That would be the best research to have all same bullets and barrel lenghts.

.308 is not a caliber available in the AR-15 platform, only the AR-10 platform.  So let's drop that one.   I have had 6.5 Grendel AR-15s since Alexander Arms started making them over 8 years ago.  I love everything about the platform except the magazines.  The C Products magazines for the Grendel are okay and vary quite a bit in quality from batch to batch.  They may have gotten better, but I have bought quite a few crappy ones with bad welds and poor finishes over the years.  

I wish someone else would come out with a top notch magazine for the 6.5 Grendel.  

I would take a 6.5 Grendel anyday over a 6.8 even with a spec II chamber.   I use the 123 grain Lapua and 129 grain SST rounds exclusively from Alexander Arms and they are excellent rounds.

Not at all how it actually works.  I have 37 deer kills nearly all with A-max 168.  Deer do not have a shoulder like yours.  easy to punch through both. Although beter t ogo right behind them and spare the meat.    I do my own butchering and always check out the wound. Bullet has gone clear through every time no matter what.  some fragments left sometimes, but most of the bullet exits and with plenty of energy.  Balck Hills loads A-maix in their hunting line, I had to read online that it wasn't a good hunting bullet long after I proved itself in the field.  

Part two that you do not understand, deer are not wired like us. you can take out the heart and both lungs and they still run away.  Only a spine shot drops them.  Due to CWD I don't take spine shots, so all of my deer run away.  I just start counting, it seems like forever, but it's 5-8 seconds and they go down having bled out, although most of the blood is still inside the chest waiting to spill on your boots.

The amount of ignorance in this post is staggering.

It didn't.

Snipers use OTM because it's ballistically  superior, not for terminal effectiveness.  In fact, SMK usually acts like ball in flesh.

The 6mm Optimum beats them both!!


Left to Right:  5.56, 6mm Optimum, 7.62x51


Caliber                        5.56 NATO    6mm Optimum    7.62 NATO
Bullet weight                  62 gr               100 gr                147gr
Velocity @ 0m              3100 fps          2900 fps            2800 fps
Energy @ 0m               1323 ft-lb        1867 ft-lb           2559 ft-lb
Velocity @ 1200m       913 fps            1149 fps             990 fps
Energy @ 1200m         115 ft-lb           293 ft-lb            320 ft-lb
Flight time to 1200m   2.63 sec           2.21 sec            2.54 sec
Deflection @ 1200m   240 inches     151 inches       200 inches
   (in 10 mph wind)
Maximum trajectory   365 inches      244 inches       332 inches


I remember first reading about this cartridge in one of the special weapons magazines in 2001.  I wonder why it never took off?  It looks like the best of all worlds!

6.5 Grendel is the next best, the british figured that out 50 years ago.

just my opinion, of the 3, i really think that both the 6.5 and 6.8 both try to do what the 308 does and neither really accomplishes that.

the grendal attemps to extend the range of the ar15 and does that, but falls short on energy and velocity long range of a simalarly conifigured ar10
the 6.8 attemps to put more energy on target  from an ar15, and does that but has significantly less range than a 308

both are specialized tools that i see fullfilling a narrow window, while i have a couple SBR's and think they are cool, i honestly, through my time in the Marines, through today, have never really found myself needing 4 inches less of barrel.

with an 308 yeah, you are going to have deal with the weight issue, which for me isnt an issue, i now prefer my LMT mws carbine to my mk18 clone as it allows me to hammer stuff with 155amax's as well put rounds realitivly accurately out to the 1000 yard mark, with todays, muzzle breaks, you can pratically run a 308 as fast as a ar15.

add in the endless supply of brass and projectiles and a can shooting plinking ammo for around 25 cents per round. with both the 6.5 and 6.8 there is really no plinking ammo or components availible, so while reloading can bring down the cost of shooting in both those callibers, i can shoot m80 projectiles for around 12 cents per bullet, where as your are going to be paying at least3 times that for the other two

so i can go out to for a weekend and blow off a thousand rounds for around 250 bucks, or go out each weekend a mounth and shoot 200 rounds per season and still spend less, than it would cost to just buy the 1000 projectiles for the other two.

Not exactly AR15 mag length there...



Nick

There's a whole lot of hogwash in this post.  

First off, FMJ bullets fired from rifles usually do not penetrate nearly as far as most of the bonded and copper solid hunting bullets manufactured today, so your point about penetration is rendered moot in those regards.  Copper and bonded bullets will pass all the way through (or nearly) most light and medium game animals.  Secondly, if you want to actually kill/incapacitate your target in a quick and humane manner, you're not going to use bullets that are either A) unpredictable in their performance once they encounter tissue or B) do not penetrate deeply enough to disrupt tissue and cause major damage to organs.  All you need to understand that is to view the FBI tests and specs that are out there (can apply to hunting as well as to humans).

In short, use the right bullet for the right job.  On top of that, use the right platform and caliber for the right job.  The A-Max is capable of killing deer and such when used for hunting purposes, but that is not it's intended use (possible vs. probable).  There are far better bullets out there with superior performance on game/tissue that are just as readily available and proven.  Use them, and use the wealth of information on this board to your advantage....

Your post contains a high amount of sophomoric tripe, which has been proven otherwise time and again....

Every neophyte on the planet quotes that when they're trying to make a point and lack the knowledge and credentials to do so.

See Hague Conventions....  

Ive shot a few IN. white tails that drop right on the spot !  head shot, and heart

I was torn 6.5 VS .308 after looking at brass cased ammo prices I opted to go .308 for now.   Once I have all the guns I want set up the way I want in 5.56 and .308 I will start looking at a 6.5 build just not sure if I wanna go SPRish or SDMish for rifle pattern.

I know that, but I find it easier to ask the person to find what they claim is there, when I know it's not.  Must be my passive/aggressive side showing.


Also +1 for use of one of my favorite words.  Right up there with troglodyte and meretricious

Who cares?  You can't use standard mags for the other two anyway (which was originally supposed to be a selling point of keeping them the same length) so what does it matter if the mag is a little longer?  

Yes, he is! The 140 SSA/Berger ammo is the current long distance target/hunting round for the 6.8. A 1000y round.
Hornady was a bad choice for comparison for the 6.8.Since Hornady loads to the outdated SAAMI Specs. SPC II ammo would be better for comparison. He should have used SSA & Wilson Combat ammo.  In addition, look at how many companies make 6.8 & how many make 6.5G.
Also, don't forget Tula & Federal coming out next year with 6.8 ammo.
No, I'm not going to bring out the 6.8 bullet chart. It is outdated anyhow.

As for the 6.5G not as popular: IMHO - As you said - It goes back to Mr. Alexander licensing the trademark & loosing a big momentum swing with other companies that make ammo & uppers/barrels for many years. Yes, he opened it up recently. Where as the 6.8 has always been open source. The question is: Is it too little, too late in a tight economy?
As for military- There were some feeding worries early on. Plus it won't fit in a standard metal belt link (Forget the mil # of it).

The 6.5G is a very good round. It is close to the 6.8 in many categories. As stated has higher BC for 500+ yards advantage.( Except for the fore mentioned 140 SSA/Berger ammo.) Although, factory loads & availability is lacking.

Also, the 6.8 was designed for a SBR, 16" barrel being the most popular it also being a sweet spot for the 6.8. The Grendel is at it's optimum in a longer barrel. The hunting ranges are very similar. Although, there is data out there that the 6.8 does very well with AA200 out of a 24" barrel.


The 308, Weight issue & it uses the AR-10 platform (which has propitiatory issues from co. to Co. IIRC). Which is more expensive than the AR 15 platform. But, a very good all purpose bolt action. Even at that it is very good at all around hunting & target shooting.


Very well written OP. But, unfortunately it does not use the best examples for the 6.8.  Which basically negates the comparisons.

I typically have the same response as you, but now I'm more of a "step on your neck and tell you how it is" kinda guy....

ANNNNNNNDDD, this is where I tune this thread completely out....it had such promise.......

Try Kies magazines, I had good luck with them!

My bad!

The Hague Convention of 1899, Declaration III, prohibited the use in international warfare of bullets that easily expand or flatten in the body.[3] This is often incorrectly believed to be prohibited in the Geneva Conventions, but it significantly predates those conventions, and is in fact a continuance of the St. Petersburg Declaration of 1868, which banned exploding projectiles of less than 400 grams, as well as weapons designed to aggravate injured soldiers or make their death inevitable. NATO members do not use small arms ammunition that is prohibited by the Hague Convention.

Anything else?

I have been following along reading comments (many good ideas, some not so helpful) and I feel that if you are looking for info on what AR-15 (or upper) to get you may be lost at this point.  Let me get back to the “purpose”:

1.If you are on a limited budget (maybe only able to purchase one) and looking for an AR-15 (or to add an upper to your existing platform) to serve as many needs as possible (cost per rd, recoil, range, accuracy, weight, small to medium sized game), I think the 6.5 Grendel is the best choice.

With that said I am NOT saying:

1.It replaces or is better than a .308.  My point was to ONLY state that one could get similar range and energy to a .308 on an AR-15 platform.  That was something I was looking for.  RANGE (effective)on an AR.

2.The 6.8 SPC is BAD, I just think you can serve MORE needs for less money ($12.50 a box of 20) with a longer possible range.   I am sure the 6.8 SPC is an excellent round.  As someone pointed out, ALL guns are great.  I have a 7.62x39 AR and love it.  That is a GREAT round but is limited.

I can’t spell (lol), it was NOT the Geneva Convention that is the reason NATO does not use HP, you CAN kill deer with A-MAX (maybe not the best in some opinions), deer are NOT human and have different anatomy, HP are destructive rounds to flesh (as are all bullets), different bullets for different applications, Grendel rounds are ONLY offered in HP (wolfgold) and A-MAX (Hornady) from the manufacture that I have been able to find and PURCHASE (that was my point – which would I rather use on a hunt, wolf or hornady), 6.5 Grendel will NOT replace a .308 but gives an AR-15 user a good alternative.  

If I could only afford to purchase ONE AR-15 to serve ALL my needs it would be the 6.5 Grendel.  THAT WAS MY POINT.  Lets try to keep our accuracy and stay on target for those looking for helpful info on a weapons purchase.  I wrote this for a friend who likes to take his daughter deer hunting and was looking for an alternative to the 5.56 and is on a limited budget.

This is ONLY my opinion!

Good point, however I just looked it up and $29.95 per box of 20 I made my point in cost.  I can get similar results or better with the $12.50 box of 6.5 Grendel ammo  @1000 yards.  One of my MAJOR points was cost per rd.

I dont think the 6.8 was meant to replace the 7.62. It was meant to be a better alternative than the 5.56 as far as stopping power. It is an assault rife cartridge and was never design to be long range. I have both a 5.56 and 6.8 like them both. If I were to shoot long range I would go with the 7.62.
Just a little note by the way, as to why I went with 6.8.

12.5 in barrel with a 85gr round at 2950 shoot sub moa.

This thread is full of fail.

WeaponsProfessor, thank you for your service, but much of the information you are providing is in error, as several folks have pointed out.  With a screen name like that, I hope you would be more diligent in what you are espousing.  Perhaps you need to go back and review modern research in this area.

I would say poorly written based on the info he presented. I.e. he only looks a certain "facts" for each cartridge just to prove the 6.5 is best (barrel length, excluding certain ammo, platform issues).



I thought we have done this before?



 

155 amax has the penetration for deer, I've killed 3 with it from my .308.

Thank you good sir.