Da..it, Don't shortchange me! 6.5 Grendel vs. 6.8 SPC

[autobahndriver]

I don't want another compromise round (6.8 SPC)


The 6.8 SPC is a "limiting" cartridge in that it's effectiveness is less at longer range.
I don't want another cartridge that limits me in some way.

The 6.5 Grendel can be a good round for some of the long ranges we are now seeing in Afghanistan.
Why go to a 6.8 SPC - good for short range - and then find ourselves wanting a good long range shooter as well as short range terminal performer?

Energy delivered are similar between the 6.8 SPC and 6.5 Grendel at short range and they are similar sized bullets.
At longer range 300+ meters, the Grendel significantly outperforms.

Remember that our situations will continually change and we will find ourselves wanting.

 

[autobahndriver]

Ballistics Comparison:

6.8 SPC / 6.5 Grendel
Sierra 115 gr / 123 Scenar Lapua
.340 BC / .542 BC

2422 / 2427 fps at 100m
1498 / 1609 ftlb at 100m
+6.06 / +5.76 in drop at 100m
1.20 / .90 in drift at 100m (10mph)

1916 / 2102 300m Velocity
938 / 1206 300m Energy
0 / 0 300m Drop
12.05 / 7.49 300m Drift

500meters:
1488 / 1803 Velocity
565 / 888 Energy
-52.41 / -43.73 Drop
37.8 / 22.41 Drift

….and the 6.5 Grendel just gets better compared to the 6.8 SPC as range increases.
At 1000m the Grendel still has 1222 fps Velocity and almost twice the energy as the 6.8.

Both the 6.8 SPC and 6.5 Grendel weigh 11.5 lbs per 300 rounds.
The 6.8 SPC and 6.5 Grendel have similar recoil (slightly more than a 5.56)
Both the 6.8 SPC and 6.5 Grendel can be used with existing AR15 lower assemblies.

The 6.5 Grendel is better on all accounts – why is there any argument???

 

[ChiefPilot]

I don't want another compromise round (6.8 SPC)

Then use 7.62x51. It's got more short- and long-range energy than eithe the 6.5 or the 6.8, it's less expensive than either, and it's readily available. AR-10 type rifles are readily available as well, as are a number of bolt, pump, and even lever action rifles in the caliber. Problem Solved.

I just don't understand the hoopla about the 6.5/6.8 rounds. If you want more than 5.56 has to offer, just get what you want - a 7.62.

 

[sumpnz]

I just don't understand the hoopla about the 6.5/6.8 rounds. If you want more than 5.56 has to offer, just get what you want - a 7.62.

I believe the hoopla is that the 6.5 gives you almost everything the 7.62x51 does, but with less recoil and less weight. Also, the 6.5 with the 144 grain bullets, actually outperformes the 7.62 beyond, I think, 400 yards thanks to it's really high BC.

autobahndriver, do a search here on the 6.5 Grendel and you'll find all the info yuo ever wanted, and about every opinion possible expressed on the cartridge.

 

[Grump]

Well, 7.62x51 doesn't make sense militarily. The Grendel can give you at least equal wind drift, and even better, than M80 ball at extended ranges, with very little decrease in terminal energy and virtually the same trajectory.

And M80 ball does that while using MORE powder, MORE brass, copper and lead, LARGER primers, and MORE shooter fatigue. Go to the better 7.62x51 loads like M852 and M118 LR and all those disadvantages become slightly greater, and in enough quantity to make a difference for strategic considerations (more shots per pound of metals ore, greater shipping costs per shot, and more weight on the Grunt for the same combat load of XXX rounds).

The Grendel can make the promise of the M14 doitall compromise rifle actually attainable, with better downrange performance.

What I want to know is whether the reported problems of "accuracy going to pot at pressures bringing the desired velocities" problem of the 6.8 have also cropped up for the Grendel. Anyone?? Anyone?? Bueller??

 

[Sam Adams]

A great website related to the 6.5 Grendel is http://www.65grendel.com/

Personally, I prefer the 6.5 Grendel vs. the 6.8 SPC based on ballistics. The biggest thing going for the Grendel is its BC - this is pure mathematics with which the SPC proponents can't argue. It is simply a better bullet, and the round itself has been optimized from a very accurate benchrest round so as to operate in the M16/AR15 family with minimal, if any, problems. If I could afford it, I'd have already bought either an upper or a whole rifle, together with reloading gear, brass and bullets. I also look forward to this round being developed for a boltie, as it is seriously accurate.

However, the odds of either round being picked as a replacement for the 5.56 mm are small. The latter is considered "good enough" by those in logistics who aren't in combat, plus there is just a lot of inertia in any large organization (esp. government). I'd love to see either round picked, as both are far superior to the 5.56mm (the only reason for this round to be good is very high velocities, which aren't attained in the short-barreled rifles being handed out lately), but of the 2, the Grendel is better. JMHO.

 

[ChiefPilot]

Also, the 6.5 with the 144 grain bullets, actually outperformes the 7.62 beyond, I think, 400 yards thanks to it's really high BC.

True, but the 7.62 with 175gr bullets is better still. Check out the ballistics chart for the 6.5 Grendel - the 7.62 still holds the energy advantage at 1000m.

For my own personal use - the amount of brass, power, and lead doesn't matter as I can buy 7.62 for far cheaper than I can 6.5 or 6.8. For the military, I'd just as soon keep them using the 5.56 and instead put the money towards something like this or this.

 

[sumpnz]

The differences in velocity and energy (for the 144 grain 6.5mm and 175 grain 7.62mm) past 600 meters are academic. Given that very few soldiers will take shots even that long I don't think the small differences really matter (it's only 10 ft-lbs difference at 1000 yards - variations from shot to shot can be bigger than that). Besides, I was intending to comapre against the M80 ball rounds (147 grain). I suppose it would be more appropriate to comapre that round to the 123 grain load for the 6.5. In that case, by 200 meters the 6.5 is going faster than the 7.62, and somewhere between 500 and 600 meters the 6.5 takes over in terms of energy. At 600 meters the 6.5 has a 6" and 10" advantage in drop and drift respectively.

As far as cost goes, were the military to adopt the 6.5 Grendel it would drop in cost very quickly to about that of what 7.62 NATO currently costs. Right now it does not have the economy of scale working to its advantage.

For my own personal use - the amount of brass, power, and lead doesn't matter as I can buy 7.62 for far cheaper than I can 6.5 or 6.8.

Yes, but we are mostly talking about the military use of the round. For them, weight is a very high priority. It was one of the big reasons they went from the .30-06 to the 5.56mm in the first place for general infantry use.

 

[JShirley]

Hooah! Carrying stuff sucks. Lightweight ammo good. John smash!

 

[Preacherman]

Don't forget that a very, very important factor in the design process for the 6.8mm. round was that it had to be able to fit as many rounds as possible into a standard M16/AR-15 magazine. Thus, the cartridge is narrower than the 6.5 Grendel, and more of the former can be fitted into a standard M16 magazine than the latter.

Makes sense, from a military point of view, no?

 

[sumpnz]

Preacherman - Well yes, but if they tooled up for 6.5 Grendel production they could just make slightly larger mags to fit the same number of rounds, and when they modified the existing mags, they could easily restrict those to training use only until they wore out, or sell them unmodified as surplus. So long as the AWB expires, and is not brought back in near term there would be no problem with that.

 

[TODD3465]

As far as I know the 6.8SPC was develped with SOCOM and wide spread military use will probably be non-existant.

However it would probably have a better chance at being adopted as it will be getting more exposure through actual combat use than the 6.5Grendel.

 

[sumpnz]

Well, considering how much better the 6.5 Grendel performed at Blackwater, I would imagine that SOCOM might be at least somewhat interested in field testing of that round too. Certainly if I were in charge of those decisions that would be my approach. Whether or not they actually do so is another matter entirely though.

Personally, if I can ever scratch up the cash to buy an AR-15, and the cash for an upper in either 6.5 or 6.8, I would choose the 6.5. And if I had the cash for two uppers, I'd get one in 6.5 with an 18.5" carbine barrel, and one in 6.5 with a 24" or 28" match barrel. And if I really had too much money to spend on AR conversions, I'd probably go for a 50 Beowulf upper (more to frighten DiFi than anything else), and maybe some other calibers like 22lr (for cheap practice), or 9mm, 40S&W and 10mm (since I like the idea of pistol caliber carbines as companions to a sidearm). But I doubt I'd ever bother with a 6.8SPC upper. I just see much point (for myself) for such a limited round that is matched or beaten by the Grendel with very little lost on the compromises that are made.

 

[TODD3465]

The makers of the 6.5 can blow their horn about Blackwater testing it all they please but the 6.8SPC round is what is being used by the military not the 6.5.

Right now a major ammuntion company (Remington) is starting to crank out the 6.8SPC and they have 3 versions of the ammo that will be available to civilians pretty soon.

Myself I don't have any personal interest in either one. Until the military actually adopts sometrhing new I'll stick to .223 and .308 in my semi-autos.

 

[sumpnz]

(Remington) is starting to crank out the 6.8SPC and they have 3 versions of the ammo that will be available to civilians pretty soon.

Yeah, and they're all 115 grains AFIAK. Just a matter of whether they are FMJ, soft point, or whatever.

The big thing that I like about the 6.5 Grendel, regardless of military acceptance, is that it can take 90-144 grain bullets. That makes it much, much more versitle. The 6.8, which is basically a member of the .270 family, can only go up to 115 grains. If I wanted a .270 for hunting, I'd go with a .270 Wincester, which at least allows for bullet weights up to 150 grains (possibly higher, but that's as heavy as factory loads typically go).

The makers of the 6.5 can blow their horn about Blackwater testing it all they please but the 6.8SPC round is what is being used by the military not the 6.5.

And, as I mentioned before, I think that's a mistake. When I'm king of the world all such idiocies shall be recitified. Until then, I'll pin my hopes on commercial success of the 6.5 Grendel. And let's face it, the 6.8SPC just will not compete in the market place based on its performance. I don't know what 6.8 uppers are going for, but even if the Grendel uppers were $200 more, I'd still bet on the Grendel winning the war for the wallets of consumers.

 

[autobahndriver]

Preacherman:

Don't forget that a very, very important factor in the design process for the 6.8mm. round was that it had to be able to fit as many rounds as possible into a standard M16/AR-15 magazine. Thus, the cartridge is narrower than the 6.5 Grendel, and more of the former can be fitted into a standard M16 magazine than the latter.

The 6.5 Grendel will fit the same amount of rounds in the same magazine as the 6.8 SPC. There is only the thickness of a sheet of paper difference in case diameters!

 

[autobahndriver]

The makers of the 6.5 can blow their horn about Blackwater testing it all they please but the 6.8SPC round is what is being used by the military not the 6.5.

The military will be using the 6.5 Grendel as well. Spec Ops has great latitude in what they choose to use. Example: H&K SOCOM (MK23) was developed by military contract for US Spec Ops use yet various Spec Ops groups still adopted different pistols (Seals - Sig due to being more compact).

Now if we could get a better round adopted for the rest of the military!

I think the major selling point for the military would be one round to replace both the 5.56 and 7.62.

The 6.5 Grendel performs very close to all 7.62 rounds in energy delivered but has better ballistics and lighter cartridge weight.

I plan to get a personal 6.5 Grendel upper.
I am promoting further testing of the 6.5 Grendel currently within the military.
I will promote adopting the 6.5 Grendel within the military if use over the next couple of years does not show any problems.

 

[autobahndriver]

Ballistics of 6.5 Grendel compared to 5.56 and 7.62 NATO:

6.5 Grendel / 5.56 NATO / 7.62 NATO / 7.62 NATO
123 S.Lapua / M262 / M80 / M118LR
.542 BC / 340 BC / .418 BC / .496 BC

2750fps / 2600fps / 2700fps / 2500fps Muzzle Velocity
1293ftlb / 1846ftlb / 2379ftlb / 2429ftlb Muzzle Energy

2102 / 1957 / 2051 / 1971 300m Velocity
1206 / 655 / 1373 / 1509 300m Energy
7.49†/ 11.72†/ 9.48†/ 8.77†10mph Wind Drift

1803 / 1521 / 1676 / 1661 500m Velocity
888 / 396 / 917 / 1072 500m Energy
-43.73 / -50.18 / -45.73 / -49.81 500m Drop in.
22.41 / 36.76 / 29.03 / 26.44 10mph Drift

1222 / 954 / 1063 / 1113 1000m Velocity
408 / 156 / 368 / 481 1000m Energy
-422.87 / -591.67 / -491.29 / -497.96 1000m Drop
107.83 / 182.73 / 144.55 / 127.31 1000m Drift

300 rounds ammunition weight:
6.5 Grendel w/123 S.Lapua – 11.5 lbs / 300 rnds
5.56 NATO M262 – 9.0 lbs / 300 rnds
7.62 NATO M80 – 13.8 lbs / 300 rnds
7.62 NATO M118LR – 15.0 lbs / 300 rnds
6.8 SPC same weight as 6.5 Grendel

*this is 20" barrel information - shorter barrels give a greater advantage to higher BC bullet and a case closer to short magnum in shape.

 

[ChiefPilot]

Ballistics of 6.5 Grendel compared to 5.56 and 7.62 NATO:

Source? *EVERYTHING* else I've seen acknowledges that a 175gr 7.62x51 load is superior to the 6.5 Grendel out to 1000m. If you have new information comparing factory loads, I'd be interested in learning more about it.

 

[autobahndriver]

The Ballistics table above is correct: Yes, when you consider terminal energy the the 7.62 M118LR round delivers more energy at under 1000m ranges than the 6.5 Grendel (superior as you stated above). The 7.62 NATO M80 is surpassed by the 6.5 Grendel at 600m+ in energy delivered.

The 6.5 Grendel, on the other hand, is superior in drop, drift, and accuracy at all ranges.

It is a trade-off:
6.5 Grendel advantage 50% less recoil (7lbs vs. 14lbs)
6.5 Grendel advantage higher BC, less drop, less drift, better accuracy.
6.5 Grendel advantage less ammo weight.
6.5 Grendel advantage can be used with existing M16/AR15 lowers.
7.62 NATO M118LR advantage 19.8% more energy at 300m, 17.9% more energy at 1000m.
7.62 NATO M80 toss up vs. 6.5 Grendel: 6.5 Grendel 9.8% more energy at 1000m, 7.62 M80 13.8% more energy at 300m.

Not a bad trade in my opinion.

 

[Grendelizer]

TODD3465 wrote: "The makers of the 6.5 can blow their horn about Blackwater testing it all they please but the 6.8SPC round is what is being used by the military not the 6.5."

Todd, I've checked and doublechecked with my sources and the 6.8 SPC is NOT "being used" by the military. Furthermore, a Remington employee emailed this on July 6, 2004: "The round is NOT being used overseas by anyone despite what you might read." (Check it out for yourself; search this forum for the thread "More 6.8SPC Info.")

And let me be clear: I'm not against the 6.8 SPC being used overseas. If it is, it is. Let the facts stand. But I'm very much against promoters of the 6.8 SPC IMPLYING that it's the hot, new military round in order to SELL STUFF to impressionable guys who want to be cool.

Todd also wrote: "Right now a major ammuntion company (Remington) is starting to crank out the 6.8SPC and they have 3 versions of the ammo that will be available to civilians pretty soon." What's your source, Todd? Remington's advertising? Wait, they themselves are not even advertising it! The gun rags? Months ago, Gary Paul Johnston wrote in Soldier of Fortune that Remington can't make it fast enough. Are you one of the millions who've bought it up? "No," you say, "but the military's been buying it all!" Are you sure? Then why did the Remington source say (this July!), "The 6.8 thing is moving along but slowly. The only significant ammo we have sold has been to Barrett as far as I know"?

Well, I'm not going to get into what my sources say about the future of the 6.8 or what my personal opinion is, but let me give you some advice: You'd do well to wait on buying an 6.8 SPC gun or upper until you know FOR SURE that ammo is definitely on the shelves. That's all. If it shows up, it shows up. If it doesn't show up and you're stuck with an upper, don't come whining to me!

John

P.S. If your adoption of the 6.5 Grendel for yourself depends on whether some special operators are using it, then let me remind you that the 6.8 SPC isn't the only game in town. I am allowed to say that the 6.5 Grendel is being used by "select members of the military community."

 

[TODD3465]

You can try and push the 6.5 Grendel all you want but your just ignoring what SOCOM wanted in a cartridge.

And as far as I know NSWC-Crane did not include the 6.5Grendel in it's list of calibers for an improved SOF combat rifle.

Here's a link look for yourself:

http://www.thegunzone.com/556dw-5.html


Go down a little more than half way and you'll see the spec sheet for the proposed rifle

Then just go further down to see mention of the 6.8SPC as the chosen round.

 

[sumpnz]

All it says is that the round had been "unveiled" and is intended for this use. It doesn't say that will be chosen, let alone that has been chosen, to replace 5.56NATO for SOCOM.

I'm not trying to put down the 6.8SPC, as I do see it as significant improvement over the 5.56mm round, but we just simply don't know what, if anything has or even will be chosen in the next 10 years to replace our venerable poodle-shooter.

I do, however, stand by my assertion that the 6.5 Grendel will win out in the "civilian" marketplace as a target shooting, hunting, and SHTF round when compared to the 6.8SPC. That, of course assumes that the military adopts neither cartridge. If they do choose one of those rounds, the other will likely fade into obscurity barring some marketing blitz to get it going on a commercial scale.

 

[autobahndriver]

The latest news from The Gun Zone on the SCAR is:

NSWC-Crane releases "Draft Performance Specification: SOF Combat Assault Rifle Light." The caliber conversion requirements for the SCAR-L have been removed in favor of optimizing the weapon for the use of 5.56x45mm ammunition. (The proposed caliber conversions, such as 7.62x39mm, are instead intended to be passed along to the larger 7.62x51mm SCAR-H.)

In addition, their performance threshold is 1.0 MOA at 300 yards and performance objective is 0.25 MOA at 300 yards. Original performance objective was 0.5 MOA at 400 yards - don't know if this is still in effect.

If they change again and allow other than 5.56 to be looked at, the 6.5 Grendel has the best ability to meet the performance objectives! The 6.8 SPC is only making the cutoff threshold currently.

Unfortunately, the current plan is to go with 5.56 for the light weapon
Once again no real look at improving the 5.56.

The Grendel may have a shot at the heavy version (SCAR-H) but the 6.8 SPC has no chance as it cannot compete with anything at long range.

 

[Zak Smith]

What requirement does the SPC "only [make] the cutoff threshold"?

Bullet drop is orthogonal to accuracy.

-z