6.5 Grendel vs. the .308

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How about using the same ones I did so that we can see how your program compares to factory published load data? Of course you are showing trajectory and not downrange velocity and energy so it still doesn't help much.
 
Here you go:

4vgwn7.jpg


The 120gr Grendel cleans the 110SPC's clock -- about the same as the SPC cleans the 90gr Grendel.
(It's a mass/energy retention thing all round.) ;)
 
Interesting. I would love to know what rifling twist and barrel length these are based on. Is that something you enter yourself? I have heard the 6.8SPC velocities have improved greatly since they started using a slower twist rate of 1:11. It would also be nice to see the two with the same weight bullets.
 
My Grendel is 1:9 and I'm getting 2,575fps (Oehler chrono'd) out of a 19.5" barrel using commercial (AlexArms) 123gr Scenars. (Handloads are hitting 2,550-ish).

Good ballistics/info for the 6.8SPC is found heree:
http://www.frfrogspad.com/68spc.htm

and here:
http://www.bvac-ammo.com/images/pdfs/RifleBallisticsData.pdf

...both of which are consistent with other published/DoD values.

Comparing the two should start with usable case capacity after the bullet is seated to magazine length. The Grendel using a 123gr anything gets to use about 28.0gr H2O case volume. The SPC optimizes on ~115gr bullets leaving 27.6gr H20 volume. This lighter-weight bullet enables the .277 SPC to roughly hit/equal the heavier-weight .264 Grendel velocities, but at the cost of a much less ballistically-efficient projectile at range
 
THE OP DIDN'T ASK ABOUT THE 6.8.

The issue is this:

From what I have read about the 6.5 Grendel it would seem that it would be more popular give its accuracy and range

And as was already said, it would do well to study the ballistics of each quite a bit more. The simple fact is that most data given on calibers are not baselined with the same rifle, barrel length, or ammo. You get a variety of each, and some study is needed to sort out the bias, BS, fanboyism, marketing, and agendas.

Companies who sell any of the guns and ammo are generally held in respectful suspicion, after all, they are trying to sell you something. Fanboys generally exhibit the affects of testosterone poisoning, it's entirely a locker room measuring contest to them, data is what it's all about.

From the perspective of what tool is better, here's the straight scoop: in the AR, the 6.8 is a great killer under 500m, the 6.5 will punch paper very precisely out to 600m, and the .308 will still kill people at 850m. If you try to use any of them for a different purpose, be very sure you are going to have to accept compromises, understand what they are, and whether it's going to affect things adversely. If it's a matter of exploiting the optimum performance, none will do what the others do. They are all designed and purpose built to do different things, and none can hold a candle to the .50BMG.

Of course, no one would want to shoot one of those from a 14.5" barrel for a full 30 round mag, either.

IBTL.
 
Ok, we've established that both the .308 and the 6.5G are good rounds at distance. I use the term 'distance' as a generic term, generally between, let's call it, 400-600 yards. Someone will yell at me for that, and I'm ok with that.

Perhaps it could come down to price, but if we go down that route, we have the following conundrum:

6.5G uses AR-15 lowers and components. AR-15 parts are generally more common and lower-priced in comparison with .308 parts. But...

6.5G barrels aren't exactly common, and only a few manufacturers are producing them, so maybe the cost advantage of AR-15 parts is offset by the barrel price come build time.

Oh, and Tirod...bring me the 14.5" .50 BMG 'carbine'. I'll throw a red-dot on it and we'll hit the range. I'm pretty sure a 30-round mag would be about five feet long, but I'll deal. :D
 
THE OP DIDN'T ASK ABOUT THE 6.8.
So noted (again) ;)
The M118-loaded 7.62NATO in an M-14 cleans all clocks.
There endeth the lesson.

except.... it's also heavier, more unwieldly in a barfight, climbs out of control on auto fire (even 3 round bursts -- ask how I know), the gun & ammunition weighs a ton when carried with all the other 110+ lbs of gear/armor in the mountains of Afghanistan, and it's currently logistically unsustainable as a main battle rifle.

The current battle rifle is just great in a bar fight and just about all the other aspects mentioned above... except... it it runs out of gas right at the range the bad guys are choosing to engage our troops. (Ask how I know)

So it's not unnatural that the argument would devolve to options that cut through to the middle ground.

As to the Grendel being limited to being a "great paper puncher," is there some experience that could be posted here?
 
Simple answer to OP's specific points in his question... Yes, 6.5 Grendel have a flattery trajectory and is more accurate. However, .308 is flat enough and accurate enough for any purpose you are likely to need to use it for out of an AR platform. It is also a larger, heavier, and more powerful cartridge with all the benefits that provides for hunting, combat, and defensive use.

So basically if your goal is target shooting, get the Grendel. If you goal is almost any other use, general use, or mixed use, then .308 is just way more versatile..... And of course a fair bit cheaper to shoot too, and if you intend to shoot much at all ammo savings will quickly exceed hundreds of dollars of extra up-front costs.
 
6.5 Grendel vs. 6.8 SPC

"Also, as for barrels being comparatively priced, show me. I haven't found a good high quality 6.5G for under $450 or so when a good high quality 6.8 barrel will sell for around $250."

"slappy", are you "conveniently" forgetting the PM I sent to you and the PM you sent to me in response the day BEFORE you wrote this?

In case you have, what I wrote was "I was just on the Alexander Arms website looking for their "Billet Upper" for my 28" barrels and the lowest priced barrel I noticed was just $260... MidwayUSA prices started at $279.99."

TEN dollars difference is hardly the $200 difference you wrongly repeated a day LATER!!!


"I have looked at many charts, they always seem to want to compare 6.5G 123gr bullet to 6.8 110gr bullets but I still say that they are so similar up to 400 yards that you can't tell the difference. If I am missing something, somebody show me where I am wrong."

All you have to do is look at "mehavey's" Post #20.

As I said out to "normal hunting ranges" there is not much difference. As this chart shows at 300 yards which I consider to be "normal hunting distance" there is maybe 2" LESS drop for the Grendel.

At 400 yards the Grendel has 8" LESS drop.

At 500 yards the Grendel has 28" LESS drop.

If you and "Jimro" can't see that or think those are "about the same" or "there is not much difference" between them then both of you will just have to live in your imaginary world of magic!


"It would also be nice to see the two with the same weight bullets."

The only fair way of comparing these cartridges is by getting your data from the SAME, RELIABLE source and not "picking and choosing" loads to make your favorite look better and the other worse.

I'm NOT in the habit of spoon-feeding answers to people and this subject has been brought up several times recently on this forum.

Do a SEARCH for yourself to find previous posts comparing the SAME bullet weights (or very close) from the SAME, RELIABLE source and with similar barrel lengths.

The only SAME, RELIABLE source that I know of shows the 6.5 Grendel superior to the 6.8 even with a 1.5" SHORTER barrel!!!:eek:

T.
 
"slappy", are you "conveniently" forgetting the PM I sent to you and the PM you sent to me in response the day BEFORE you wrote this?
Nothing convenient about forgetting but when you rely on pain meds to get thru the day sometimes it just happens that way, but I did forget until after I posted that last night. I am concerned that AA doesn't say who manufactures their barrels though. I have no way of knowing how they compare to the the ones we discussed. Also neither AA or the AR Stoner (not sure of quality there either) barrels on Midway come with a target crown, only threaded muzzles and I have no use for a flash suppressor on a hunting or target rifle.
The only fair way of comparing these cartridges is by getting your data from the SAME, RELIABLE source and not "picking and choosing" loads to make your favorite look better and the other worse.
Didn't pick and choose, I don't have the barrel we discussed so at this point, I don't have a dog in this fight. I posted the information I could find. There is not very much ballistics info out there for either cartridge that I can find and everywhere you do find an actual comparison it it just like I said, comparing 6.5 123gr against 6.8 110gr which doesn't help me much. I posted three different charts of the closest bullet weights I could and I as far as velocity/energy, I still don't see what all the fuss is about.
As mehavey said about his own charts, the 110gr 6.8SPC cleaned the 90gr 6.5G's clock and the 120gr 6.5G cleaned the 110gr 6.8SPC's clock. I have yet to see any fair comparisons of identical bullet weights and barrel lengths. If the information is available I don't know where to find it.
As I said in our conversation the other night, my main use is hunting, with some target shooting but not likely farther than 200yds since that is as far as my personal range goes and I am not likely to go where I have to pay to shoot.
At 400 yards the Grendel has 8" LESS drop.

At 500 yards the Grendel has 28" LESS drop.

If you and "Jimro" can't see that or think those are "about the same" or "there is not much difference" between them then both of you will just have to live in your imaginary world of magic!
Again, that is not a fair comparison with equal weight bullets and equal length barrels. Not wanting to pick and choose, that doesn't mean so much.
 
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Conversations may evolve, but going off topic and introducing something not asked about isn't.

I built a 6.8, but in the process of researching it over two years, the one thing that stood out were all the fanboys of another cartridge intruding into conversations and insisting their's was the only answer. It didn't help the OP whatsoever, it just diverted the topic and they become flamefests of ego.

As for the 6.5G, it got it's creds shooting and earning the 600m record which it held for some years. I question the background of a 6.5 fan who doesn't know this. After all, it was developed by the creator of the PPC cartridge, all of which were designed to garner long distance precision shooting records - on and in paper.

Let's get back to the topic, which is really about 6.5G being "as good as" .308. Again, study the ballistics - and use a jaded eye, because most of the data out there isn't directly comparable. Some judicious thinking is involved, loads can't be identical, and barrel lenghts alone are usually out of the norm. 26" isn't common in gun racks.

The significant difference is that a 123gr bullet propelled by less than 30gr of powder cannot and will not perform equally with a 162gr bullet pushed by 50gr. Ballistic coefficients in the respective bullets are about equal, so the bigger heavier bullet will retain more energy longer.

It's been the basic thesis of some 6.5G enthusiasts to beat the drum that their chosen One Bullet To Rule Them All can replace the .308. Somewhat silly when the originator and developers never promised it.
 
Post #5
Does anyone sell a 6.5 in the typical 6.8 price range?
This is what got me started talking about the 6.8SPC. My mistake for not realizing that it wasn't the OP who asked the question. At any rate, if anyone is interested, I called Alexander Arms, they make their own barrels but the guy on the phone couldn't even tell me what grade of stainless steel they were made from, and they all come with threaded muzzle. I have no way of knowing about the quality of this barrel since I don't know anyone who owns one. I am looking for a 20" barrel and that is priced at $320 compared to the Bison Armory barrel at $200. AA doesn't offer any kind of coating and they don't offer a package deal with gas block and tube as Bison does, so they are still a pretty fair distance apart on price as I originally said.
 
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It's been the basic thesis of some 6.5G enthusiasts to beat the drum that their
chosen On-Bullet-To-Rule-Them All can replace the .308.

No.

It does not replace the 308Win/7.62NATO for what the cartridge can do
...and that it not what Grendel aficionados espouse.

What they do suggest is that if some cartridge is to replace the 5.56
-- and have as many of the ballistic advantages of the 308 as possible
while still maintaining the dogface hump/logistical advantages of the
AR/M-x platform -- then the Grendel fills that bill.
 
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Having spent a fair bit of time contemplating the merits of the Grendel, and writing about it in this and other fora as well as on my own website, I am reasonably sure that arguing the military merits of this cartridge is a fun sport. Problem is that political and, perhaps, a few technical & logistics arguments make the sport more like that of debating on how many angels can dance on the head of a pin. We get insight from the exercise that may be useful for this and other discussions, some of which may actually pan out in the form of production hardware.

Mehavy's trajectory plots are very useful and make the strong argument that there is not enough difference in performance between the Grendel and other cartridges optimized for deer-hunting to make a difference under 250 yards. The animal is as dead either way, adequate blood trails can be expected, and the crosshairs center in the vital zone will generally make the hit absent shooter error or bizarre conditions. The 30-30 with proper bullets and zero, 257 Roberts, .243 Winchester, the .308 Winchester, the 6.8 SPC and a bunch of other cartridges have this characteristic. The Grendel and the SPC stand out because they are cartridges designed to operate on the AR15 platform.

The thing that differentiates the Grendel from the SPC for hunting and target shooting is that it does indeed have the reach to be effective over the longer ranges for both hunting and target shooting. In fact the Grendel is reported to be very effective in target shooting at the 600 yard range.
 
6.5G barrels aren't exactly common, and only a few manufacturers are producing them, so maybe the cost advantage of AR-15 parts is offset by the barrel price come build time.

6.5 Grendel barrels from Midway, AR-Stoner (ER Shaw), for $300 (I snapped one up on last summer for less) produces sub-moa results in our build.

Is it a bit more than some .223 barrels? Probably, but not by much.

Expect the prices to come down since the SAAMI standardization as the round becomes much more popular. There's just no reason for it not to go gangbusters now that AA is out of the loop.

What they do suggest is that if some cartridge is to replace the 5.56
-- and have as many of the ballistic advantages of the 308 as possible
while still maintaining the dogface hump/logistical advantages of the
AR/M-x platform -- then the Grendel fills that bill.

Yep.
Since we've finally decided to deal with the two-hour drive each way to shoot long range target(100 and 200M just wasn't a challenge anymore), the 6.5 was the obvious choice. IF we end up deciding to hunt medium game, it'll fit that bill perfectly as well. We don't "plink", and I handload, so there is absolutely no reason I would build a .223 AR anymore, because it doesn't fit our shooting "hobby".

Everyone is different, there is no "one size fits all".
 
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The only SAME, RELIABLE source that I know of shows the 6.5 Grendel superior to the 6.8 even with a 1.5" SHORTER barrel!!!

I used to own a Grendel (I won't explain why I sold it), but I was getting 2600+ FPS with an 18" barrel and 120gr AMAX's.
 
Sorry tirod, 6.5G vs. 6.8 SPC again

Slappy said, "It would also be nice to see the two with the same weight bullets." and "I have yet to see any fair comparisons of identical bullet weights and barrel lengths. If the information is available I don't know where to find it."

Again and again and again...

I'm NOT in the habit of spoon-feeding answers to people and this subject has been brought up several times recently on this forum.

Do a SEARCH FOR YOURSELF to find previous posts comparing the SAME bullet weights (or very close) from the SAME, RELIABLE source and with similar barrel lengths.


"... I called Alexander Arms, they make their own barrels but the guy on the phone couldn't even tell me what grade of stainless steel they were made from..."

Honestly, would you have had a clue what he was talking about if he had told you what grade steel?


"It's been the basic thesis of some 6.5G enthusiasts to beat the drum that their chosen On-Bullet-To-Rule-Them All can replace the .308."

Neither "mehavey" OR I mentioned this!

Per "mehavey", "It does not replace the 308Win/7.62NATO for what the cartridge can do ...and that it not what Grendel aficionados espouse."


"...I am reasonably sure that arguing the military merits of this cartridge is a fun sport."

Once again... Neither "mehavey" OR I mentioned this!


"Mehavy's trajectory plots are very useful and make the strong argument that there is not enough difference in performance between the Grendel and other cartridges optimized for deer-hunting to make a difference under 250 yards."

You totally missed the point... "slappy" and "jimro" said there is not much difference between the 6.5G and 6.8 SCP "out to 400 or 500 yards".

Mehavey's chart CLEARLY shows there is a large difference at 400 yards and a HUGE difference at 500 yards.

And, there is no point going beyond 500 yards, the 6.8 SPC is a joke!!!


"The thing that differentiates the Grendel from the SPC for hunting and target shooting is that it does indeed have the reach to be effective over the longer ranges for both hunting and target shooting. In fact the Grendel is reported to be very effective in target shooting at the 600 yard range."

Here, you hit the point...:D The 6.8 IS an adequate cartridge at normal hunting ranges. The 6.5 Grendel IS ALSO an adequate cartridge at normal hunting ranges AND FAR MORE. It is more than adequate for all uses at ranges where the 6.8 is useless. The 6.5 Grendel is a multi-use "all" range cartridge also.

Buy the 6.8 for hunting ranges and another cartridge for "other" uses or just buy a 6.5 Grendel for all uses.


"6.5G barrels aren't exactly common, and only a few manufacturers are producing them, so maybe the cost advantage of AR-15 parts is offset by the barrel price come build time."

Just how much EXPERIENCE do you have buying 6.5 Grendel barrels? I'd bet NONE.

With that "wealth of experience" how do you come up with your facts and prices?

With TWO Grendels already built and TWO Grendel barrels "in hand" for additional builds, I have never EXPERIENCED problems buying a Grendel barrel.


"Expect the prices to come down since the SAAMI standardization as the round becomes much more popular. There's just no reason for it not to go gangbusters now that AA is out of the loop."

Hope you are correct here!

T.
 
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