6.5 Grendel vs. 6.8 SPC vs. .308

dcase

New member
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)
MUZZLE 100 200 300 400 500
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)
MUZZLE 100 200 300 400 500
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)
MUZZLE 100 200 300 400 500
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.
 
You have convinced me, the 6.5 is the only way to go.
I admire your passion for it.
thumbup1.gif
 
I did. I just wanted to provide those in the "decision making" process with the info I was looking for several years ago and a lot of money later. My reviews are in my opinion completely objective and without outside influence. I have only one goal, provide the facts as I have experienced. Knowing now what I know, I would have made a few different decisions. My goal is help others in their decision. LOVE my AR's and love shooting them. There is nothing better than a fine shooting weapon (wife and kids excluded).
 
I thought many times of buying a 6.5 Grendel upper. Cool little round. Definitely better than the 6.8. Then I saw first hand how easily my RRA 223 would kill yotes and deer via 70 gr. TSXs and kind of gave up on the idea.......
 
Originally Posted By: 2muchgunI thought many times of buying a 6.5 Grendel upper. Cool little round. Definitely better than the 6.8. Then I saw first hand how easily my RRA 223 would kill yotes and deer via 70 gr. TSXs and kind of gave up on the idea.......

I completely agree! I have had no problems with the 5.56 on deer but only at 100-300 yards. I would not want to shoot a deer beyond 300 yards with a 5.56. That is what I like best about this round is the range!
 
Great post! I like all the info you put out there. For guys like myself who don't have time to do all the research and comparisons, this really helps!
 
So little difference in the cartridges at 500 yards it's a draw for me. Something about the Grendel not belt feeding is the reason our military won't use it. The Saudi Army is using the 6.8 SPC now instead of the 5.56. We took a look at the 6.8SPC but the cost of switching is too great even though the 5.56 is a poor man stopper.

6.5 is a great bullet in a Credmore or .260 Rem or even the old Swede 6.5x55
 
I agree the 6.5 is superior to the 6.8, but I would choose the 308 every day. Bullets range from 110 to 210 with proper barrel. It can shoot to 1000, but there are better choices. It also has more energy. I have thought about the 6.5, but always go back to why when a 260 rem, 6.5 creedmoor are superior. I don't intend to be contrary just stating my opinion.
 
If you reload then 6.5

If you don't then I would go with 6.8 which I did for the wife.

6.8 forum is a great info resource for the 6.8.


I love the .308 (rifle) and have been kicking around the idea for an AR platform..

Good Luck
 
I look at the 6.5 and the 6.8 as a 300yd deer round. It's pretty much a toss which one is better. I know you can do better than 300 yards but I'm talking practical..... as in a practical deer cartridge. I have a Bison 6.8 and love it. I'm even trying to talk myself into using it on a cow elk hunt this year...but, in real terms it's not a powerhouse... just a whole lot better than a .556. If I were to choose one of the calibers you mentioned, it would be the 7.62x51 every time. Of course the drawback is the heavier platform... but for raw power and versatility... the .308 is the way to go. Oh, I do have and use the 6.8 and .308 in the ar platform. The 6.5 is on the shopping list too. It's a sickness...lol.
 
Lots of info, If that is what you want get it. Not all will agree with your choice. I like the 6.5 but it has to be necked down to 6mm. Take your assesment to the 6.8 forum and see what they have to say.
 
Personally, if I want a hotter round than a 6.5/.264lbc, I'll take it on a bolt action. I really like the AR platform, but for me, the long(er) action ARs are too much of a good thing. Also too much of some not so good things - too much weight and too much money. My $.02.
 
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Lots of comments on the .308. My intent was not to say that the 6.5 would be better than a .308 but if you have an AR-15 and don’t want to spend the money on a NEW AR-10 the 6.5 Grendel is a great choice that can get you close to or similar capabilities to the AR-10 using your existing AR-15 thus saving you money and weight. My main focus was 6.8 vs. 6.5. When I was doing research to help me decide which one I wanted I thought there was a lot of “miss-information” regarding the 6.8. Example it was a better CQC round and had more “knock-down” power. There really is no facts to back this. As many have pointed out they are so close at 0-300 yards its splitting hairs. My main point is why stop then and limit yourself to a shorter range when you can have a much longer range with better accuracy? I am not saying the 6.8 is a bad round but there are a lot of people like me that were/are looking for “one” AR to serve many needs and I feel that the 6.5 does the best job of serving the most number of needs (accuracy, cost, hunting, range, stopping power). Maybe not the best choice for NATO, time will tell.
 
Originally Posted By: SwandogThese ballistics for the 6.8 SPCII beat the Grendel big time from this SSA factory load.
500 yards
1639fps
835ft/lbs

Is there enough room in a Grendel case for a 140gr bullet and powder in a magazine length OAL?
http://www.ssarmory.com/6.8_spc_ammo_140gr_VLD_Berger.aspx

Normally, I bypass most 6.5 vs. 6.8 comparisons/arguments but this little quote made me laugh.....alot. Yes, the Grendel was designed to shoot long bullets - unlike the 6.8 which they have to make special bullets for. I would like to see the 6.8 shoot a 140 gr. that was designed for the 270 Win. And yes, the Grendel shoots the 140's quite well. And yes, I have been shooting them for close to 5 years now. AA even has load data on their site. And yes, you can keep them to a COL of 2.26 or shorter (the 140 Berger, being a VLD has to be single loaded, but I use Sierra's and Hornady's anyway), unlike the 6.8 which must use a PRI mag with a COL of 2.3 - read your own link. And if you want to cherry pick certain loads, I have a couple that will blow that one out of the water, but everybody could cherry pick to death. Now, with all this about the 140, I prefer the 100 to 123gr. range, that's the sweet spot. Dcase did a fairly decent job comparing the two, apples to apples, but I don't like the 308 comparisons. I never liked the 308 comparisons, Grendelizer on 65grendel came up with that analogy years ago, but they fall short. A comparison to 300 savage would be closer. And as for the Grendel not being able to be belt fed, that is freaking hilarious. Stan Crist, years ago stated that the current disintegrating link that is used for 5.56 could be used on the 6.8 but couldn't be used on the 6.5, and over the years it has progressed into the Grendel couldn't be used in belt fed automatic firearms. It is a simple engineering problem that would require a design change, but to imply it can't be used in belt fed automatic firearms is laughable. I was shooting the Grendel before most of you ever heard of it or the 6.8. They are both good rounds, but I say this alot, and will say it again...don't try to make the 6.8 a 270 win. and don't try to make the 6.5 Grendel a 260 Rem. Now time to go pack for a long weekend of shooting and fishing.
 
I dont own a 6.8 but I do have a 6.5 grnedel and an AR-10 and both have their place. I can say that I have taken many hogs and deer with my grendel and I love it. my furtherst shot so far was 320 yds. The hog ran about 40 yards and fell over. Great little round!
 
Originally Posted By: BullmastiffOriginally Posted By: SwandogThese ballistics for the 6.8 SPCII beat the Grendel big time from this SSA factory load.
500 yards
1639fps
835ft/lbs

Is there enough room in a Grendel case for a 140gr bullet and powder in a magazine length OAL?
http://www.ssarmory.com/6.8_spc_ammo_140gr_VLD_Berger.aspx

Normally, I bypass most 6.5 vs. 6.8 comparisons/arguments but this little quote made me laugh.....alot. Yes, the Grendel was designed to shoot long bullets - unlike the 6.8 which they have to make special bullets for. I would like to see the 6.8 shoot a 140 gr. that was designed for the 270 Win. And yes, the Grendel shoots the 140's quite well. And yes, I have been shooting them for close to 5 years now. AA even has load data on their site. And yes, you can keep them to a COL of 2.26 or shorter (the 140 Berger, being a VLD has to be single loaded, but I use Sierra's and Hornady's anyway), unlike the 6.8 which must use a PRI mag with a COL of 2.3 - read your own link. And if you want to cherry pick certain loads, I have a couple that will blow that one out of the water, but everybody could cherry pick to death. Now, with all this about the 140, I prefer the 100 to 123gr. range, that's the sweet spot. Dcase did a fairly decent job comparing the two, apples to apples, but I don't like the 308 comparisons. I never liked the 308 comparisons, Grendelizer on 65grendel came up with that analogy years ago, but they fall short. A comparison to 300 savage would be closer. And as for the Grendel not being able to be belt fed, that is freaking hilarious. Stan Crist, years ago stated that the current disintegrating link that is used for 5.56 could be used on the 6.8 but couldn't be used on the 6.5, and over the years it has progressed into the Grendel couldn't be used in belt fed automatic firearms. It is a simple engineering problem that would require a design change, but to imply it can't be used in belt fed automatic firearms is laughable. I was shooting the Grendel before most of you ever heard of it or the 6.8. They are both good rounds, but I say this alot, and will say it again...don't try to make the 6.8 a 270 win. and don't try to make the 6.5 Grendel a 260 Rem. Now time to go pack for a long weekend of shooting and fishing.

I'm glad you got a good laugh but the point is it's a fact that the 6.8 SPCII can keep up pretty well with the Grendel with this SSA offering.

Most Grendel fans want to characterize the 6.8 as nothing more than a 300 yard hunting round and that the bullet can't even make it to 1000 yards. Not true. I'll agree the 6.5 has the BC advantage over the 6.8 but not by a tremendous amount. And there's nothing wrong with companies building bullets for the 6.8 which you seem to think is a bad thing. Companies realize the 6.8 SPCII is the second most popular AR platform just behind the 5.56 in sales and want to improve and refine it's capabilities. Anything wrong with that?
 
Originally Posted By: Swandog
Bullmastiff said:
Swandog said:
These ballistics for the 6.8 SPCII beat the Grendel big time from this SSA factory load.
500 yards
1639fps
835ft/lbs

Is there enough room in a Grendel case for a 140gr bullet and powder in a magazine length OAL?
http://www.ssarmory.com/6.8_spc_ammo_140gr_VLD_Berger.aspx


Originally Posted By: Swandog
I'm glad you got a good laugh but the point is it's a fact that the 6.8 SPCII can keep up pretty well with the Grendel with this SSA offering.

Most Grendel fans want to characterize the 6.8 as nothing more than a 300 yard hunting round and that the bullet can't even make it to 1000 yards. Not true. I'll agree the 6.5 has the BC advantage over the 6.8 but not by a tremendous amount. And there's nothing wrong with companies building bullets for the 6.8 which you seem to think is a bad thing. Companies realize the 6.8 SPCII is the second most popular AR platform just behind the 5.56 in sales and want to improve and refine it's capabilities. Anything wrong with that?



Did you take a close look at SSA's claims for that round? They're claiming an MV of 2400 fps. That sounds awfully optimistic considering Hodgdon's fastest/hottest load for the 6.8 is a 115 Sierra HPBT over a compressed load of 8208 running at bit over 2600. And that is running 51K psi. So SSA is sticking a near VLD profile and therefore presumable substantially longer, bullet weighing over 20 percent more in the same case and only losing 200 fps while keeping pressures from going through the roof? Somehow, even if they can extend the COAL to 2.300 as the seem towant to, I have a diffcult time swallowing that one. Sorry, I'm a skeptic.

I think the 6.8's success should be largely credited to Bill Alexander. I don't claim to know anything about who did and said what when the 6.5 G was being developed, but I think the way the Gredelistas went about licenseing and promoting the cartridge pretty much ceded the field to the 6.8. It's been catch up ever since.
 
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A lot 6.8 folks are using AA2200 which gives higher velocities and less pressure than any Hodgdon powder although H322 is close. SSA has stated they are using a powder blend to achieve those velocities and are within safe pressures.

Personally, I'm driving 120SST's at 2565 with AA2200 and that's my best shooting target bullet. I can and do seat them out to 2.300 with my PRI magazine. Still not as flat out to a 1000 yards as the Grendel but hey, holdover is just a number on a dope card as long as you know your distance, trajectory is not so important. I'm sure all the 1000 yard 6.5 shooters are using 20 MOA bases anyway.

I'm not bashing the Grendel at all and don't hate me for stating some truths about the 6.8 SPCII. Guns are guns and I love them all, even the 6.5 Grendel. lol
 
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