Originally Posted By MudBug:
Back when I got my first Grendel, a lot of the 6.8 guys were making a big deal about the fact that it had a SAAMI cert and the Grendel didn't. They also talked smack about Bill A for not seeking one. Bill A basically said something like "It's too much of a hassle, you have to be one of the big boys, and it doesn't really mean that much, the Grendel will live or die on it's performance.".

Kinda odd that the same SAAMI organization that many in the 6.8 praised as the reason the Grendel would never be anything is what almost killed the 6.8 spc.

Originally Posted By GPalmer:

I think it's more accurate to think of it as Remington's indifference to the new cartridge they introduced almost killed it. Remington promulgated the new specification, they compromised the original specification in doing so and they never went back and cleaned up their mistake with SAAMI. I think having the SAAMI specification got more people to build it, even if it wasn't the optimum specification. So far as almost killing it? I would have to go back through the selection process again, but I think if performance were limited by the original specification, I very well might have gone with the Grendel instead. With the current specifications I can fire rounds out of my 12.5" barrel which will fragment or disrupt out to 300 yards. That is a very, very effective CQB and general use weapon. With the old spec that would be sharply reduced. I'd have to run the numbers but I wouldn't be surprised if bullet disruption and fragmentation were reduced to 200 yards or less.

I personally had some trouble understanding why Constructor, Tim_W and HTR's work was really important at first. Sure just a few hundred fps of additional speed. Well, until I ran the numbers and started looking at what that meant to MY performance and the expected behavior of the bullet with a 12.5" barrel. BIG difference! that's what really sold me on the 6.8 SPC, a great CQB size weapon which could reach out and be effective throughout the most useful range.

Originally Posted By hi-tech-rancher:



GP, Your conclusion about the big difference of an extra 200-300 FPS is spot on.  Just look at the difference in the performance of 5.56 when it is fired from a 20" versus a 14.5" M4 barrel.  There is a major castration of the terminal effectiveness of the round.  This does not happen with 6.8 SPC.  You can fire the cartridge in a 14.5" weapon and get 90% of the effective velocity out of the cartridge, and thus, almost all of its terminal performance even with such a compact weapon.  This is very important to the warfighter, LEO and hunter, alike.

Originally Posted By Zhukov:This is the primary reason the 6.8SPC is still the only candidate for the military right now.

Originally Posted By Grendelizor:





Please document that statement, or kindly leave unsubstantiated rumor out of the tech forum.

Originally Posted By Zhukov:


http://ammo.ar15.com/project/Misc_Documents/Roberts_2008NDIA.pdf
 

Originally Posted By hi-tech-rancher:


John,

I'm sorry, but what you see below is nothing even remotely resembling "unsubstantiated rumor."

Zhukov, Thank you for posting this.  All of you should read this in it s entirety, and please allow me to abstract the following excerpts for you:

"Unfortunately, combat operations since late 2001 have again highlighted terminal performance
problems, generally manifested as failures to rapidly incapacitate opponents, during combat
engagements when M855 62 gr “Green Tip” FMJ is fired from 5.56 mm rifles and carbines. This
is not surprising, since M855 was not originally intended for use in carbines or rifles, especially
those with short barrels. In addition, most 5.56 mm bullets are generally less effective when
intermediate barriers, such as walls, glass, and vehicles shield opponents––this is a significant
consideration in urban combat. The decreased incapacitation potential of 5.56 mm compared with
larger rifle calibers is intrinsic to the small caliber varmint hunting roots of the 5.56 mm cartridge;
in many states it is illegal to hunt deer size game with 5.56 mm, so why do we expect it to offer
ideal terminal performance against aggressive, violent 100-200 lbs human opponents?


The above underscores my first point.  the foregoing sums it up well for you ( I am quoting Dr. Roberts):

".......anybody who has seen the actual data from the 10,000 or so test shots collected
by the JSWB-IPT at 3-10m, 100m, and 300m distances or who has read the original 331 page final
draft report dated 12 April 2006, knows that the clear and unequivocal best performing cartridge in
the JSWB-IPT testing was 6.8 mm. In addition, several 5.56 mm loads performed better than
current M855, especially from shorter barrels. This was validated by the 11 August 2006 joint
USMC/FBI Phase I Ammunition Study report that once again clearly illustrated that 6.8 mm offered
the best terminal performance of ALL calibers tested. The report also demonstrated that the 5.56
mm 62 gr “Barrier Blind” load used by the FBI and other LE agencies offered superior terminal
performance to current military issue 5.56 mm ammunition. The JSWB-IPT wrote:
 “The best performing systems emphasizing tissue damage, on the average, in this
study were of larger caliber than 5.56 mm.”
 “The 6.8 mm performance observed in this test suggests that an intermediate
caliber is the answer to the trade-off balance issue.”
 “The 6.8 mm projectile had a near optimal balance of MASS, VELOCITY,
and CONFIGURATION to maintain its effectiveness, even at a lower impact
velocity.”
 “The 6.8mm SPC is far and above, the best performing ammunition…”

This highlights, in ways more scientifically chronicled by Dr. Roberts than that which I can muster, the  attributes of 6.8 SPC which make it unique among short-action cartridges capable of fitting in an AR -15/ M-16 mag well.

1) it fits in an AR15/ M-16 mag well

2) it develops a high % of its potential velocity even in very short barrels, which allows a great degree of terminal performance to be realized even with the standard issue, 14.5"  M4 carbine.  When you use the right 6.8 bullet fired from a 20" barrel, the round can be effective up to 500 yards, increasing the versatility of fielded weapons systems.....and in fact, even a 10.5 " SMG style AR  upper can easily generate 2800 FPS with Barnes TSX's

3) The heavier 6.8 round defeats barriers better, and offers better terminal performance than many other calibers.   There are some very smart people with a very important mission testing this round and coming to this conclusion.

4) to the "average" civilian consumer who hunts, the 6.8 SPC turns his AR-15 into a highly versatile hunting, SHTF, home defense and target rifle.....all in one.  I can personally attest to its effectiveness as a hunting caliber, but I have no experience with 6.5 Grendel.  I expect it would be a good hunting round, but I would NOT expect to have a Grendel rifle that could do all of the things I mentioned in one rifle and do them all well.

There you have it.

Originally Posted By Powder_Burns:
If I am target shooting out of an AR-15 500-1000yd out, I'd opt for a 6.5 Grendel. The long range performance really makes it an attractive cartridge and all the B.C. S.D. etc. stuff reinforces its use in that application
[/span]

Make that TWO European militarys wanting to adopt the 6.8 SPC...and not the 6.5G

First the Italians...and now the Czech's....

http://www.thefirearmblog.com/blog/2009/05/11/cz-s805-rifle-coming-to-a-store-near-you-maybe/

Originally Posted By RedTx:
I have a 6.8 from ar15perfromance.com and a AA 19.5 hunter 6.5 Grendel.  I personally like both of them.  The things I shoot with them dont like them at all.  They both do pretty much do the same thing.  I find the 6.8 is a little cheaper to shoot.  The grendel has the distance.

My personal prefrence is the Grendel.  It sounds diffrent than the 6.8 when it is fired, hard to explain.  I like the way the 6.5 grendel ammo looks.  The grendel to me just has greater sex appeal as where the 6.8 looks, feels  like a work horse.

Just my prefrence.  Im not getting rid of either on of them.

Originally Posted By jjar15:


Uh ... that article doesnt say anything about any millitary wanting to adopt any cartridge.  Neither does the Beretta article.

Originally Posted By Zhukov:


http://ammo.ar15.com/project/Misc_Documents/Roberts_2008NDIA.pdf
 

Originally Posted By bwaites:


I have found AA and Wolf 6.5 ammo on the shelf at Cabelas, and I have found 6.8 Remington, (but not Silver State) on the shelves as well. Ammo for both can be hard to come by.


However, the truth is that I have yet to speak with a Grendel owner who didn't love his Grendel, whether it was a Sabre, Alexander Arms, JP, Les Baer, or a custom build. Everyone of them seems to just grin as soon as you mention shooting their rifle. None really felt like they wanted to screw with it.

The animosity between the camps is ridiculous!

Pick one, then shoot it and be happy! Better yet, buy both and see which one you like shooting more! Over time, you will gravitate to one or the other and then you will know what the best decision was!!

The antigunners LOVE to see us bicker, because they can and will use it against us, and it will start to happen soon!!

Originally Posted By Cold:


SSA just recently inked a deal for ammo in cabelas stores, so keep your peepers open, ti will be there Im sure.

style='color: orange;']I have met several people unhappy with both rounds, plenty have posted here with their unhappiness concerning each, you must not have been reading those months here.[/span] Neither round is perfect, that much is true and is not debatable, (try as you like, either camp). Anyone who thinks one is far and away better then the other, well what can I say, that person is not putting a whole lot of rounds down range a year... thats for sure.

I agree with the last portion, 100%, been saying it for a while now, and yet some people just don't that part through their head. At least we can agree on that part (in blue).

Originally Posted By bwaites:  
I was pretty specific. I don't care what I read here, or for that matter, in most places on the web. If all the people that posted they had shot this or that had actually done so, Bill Alexander would have to have built as many Grendels as Colt has M16's, and somebody would to have had to build as many 6.8's as Kalashnikov built AK's!!


Of those, the Grendel owners have been uniformly happy, and the 6.8 guys only slightly less so, and because of the chamber limitations they have.

Originally Posted By Cold:



My point is, that is subjective information (just as what I said based on who I met and  with chatted about either ctg is too) but you decided to add it to the discussion first and I am don't think it matters , how does it really help a technical talk with regards to a person deciding which to select?  It really doesn't.
I guess the few people you speak to on the phone or chat casually with face to face on the subject, does not really hold a heck of a lot of weight with respect to the topic at hand as it seems to be opinion.
I don't give a lot of cred to people I speak with who are happy or unhappy with one or the other, a person has to decide what suits them and why based on a whatever info they feel is relevant, if thats opinion, then well... what can I say, some people will be unhappy and some won't be.

Look at the majority of people posting in this thread... look at the number of people having to be edited...usual suspects, same talking points, same tired discussion.

Originally Posted By RUTGERS95:
Like someone earlier said, under 500yds your better off with the 6.8.  If your shooting farther out, your gonna use a bolt action or something in .308.

Originally Posted By Grendelizor:
The technical side of this debate can't be settled until the 6.8 SPC camp decides which 6.8 chamber will be the industry standard, the SPC I, the SPC II, or the SPC III, and until they decide which cartridge performance specifications and pressures will work safely in the chosen industry-standard chamber.

I tried debating, via my infamous 6.5 Grendel charts, technical performance standards. For the 68SPC load, I choose a Silver State Armory gen. 2 factory load whose velocities were independently verified by Gary Roberts himself. "Foul!" cried the 6.8 SPC camp, "those figures are misrepresentative!" Ex-frickin'-scuse me? Let's try that again: Latest factory load from the leading 6.8 SPC ammo maker. Independent test data. Invalid? "Oh, yes, the data is invalid," said the 6.8 guys, "we can easily achieve 200-300 fps more at safe pressures with our handloads. Try stickin' that in your charts."

For any given bullet weight, I'll give the 6.8 SPC 25-75 more feet per second than the same weight bullet in 6.5 Grendel, due to bolt-thrust and piston-area issues (muzzle velocity for lighter bullets will be skewed toward the 68SPC due to piston-area, for heavier bullets it will be skewed toward 65G because of less case intrusion). Let's call it an average muzzle velocity advantage (ignoring the effects of BC down-range) of 50 fps in favor of the 68SPC.

What I will NOT give the 6.8 SPC is a 200-300 fps muzzle velocity advantage (with performance equalling the .243 Winchester per bullet weight, as I've seen claimed). As Hi-Tech-Rancher rightly points out, this is the crux of the issue and we're, apparently, at an impasse.

The only performance specifications worth debating are independently verified factory ammo. Put another way, until the industry agrees on standardized chamber and ammunition specs for the 68SPC, it's not really worth debating.

John

| 6.5 Grendel: The Tier One AR Cartridge. |

www.65grendel.com

Originally Posted By vmpglenn:


We seem to be OK with the 5.56/.223 world having .223 SAAMI, 5.56 NATO, and Wylde chambers. It is certainly possible for a shooter to produce dangerous pressures shooting 5.56 in a .223 chamber, yet we expect shooters to know which ammo goes with which chamber. For 6.8, we have the SAAMI, SPCII, and DMR, which are direct equivalents for .223 SAAMI, 5.56 NATO, and Wylde, yet it is somehow too much to ask for shooters to know which ammo goes with which chamber...

Even better for 6.8, SAAMI chambers will eventually become extinct, whereas .223 SAAMI isn't going anywhere.

Originally Posted By bwaites:
[Why will it become extinct? Are all those rifles going to disappear? There are manufacturers STILL producing SAAMI chambered rifles.

Wylde chambered rifles are wildcats, and those people are generally reloading for their own. .223 vs 5.56 is a valid argument, except that most AR makers, (not all,  to my knowledge, but most) make their AR's in 5.56 chamberings, since .223 can safely be fired in it but not vice versa.

BUT...when manufacturers use 2 different chamberings for the same named cartridge, it does produce confusion, which does cloud the issue of selecting between the 6.5 and 6.8.

I'm sorry, but MOST people don't know the difference, and unless it is pointed out, have no idea.

Originally Posted By bwaites:

Why will it become extinct? Are all those rifles going to disappear? There are manufacturers STILL producing SAAMI chambered rifles.

Wylde chambered rifles are wildcats, and those people are generally reloading for their own. .223 vs 5.56 is a valid argument, except that most AR makers, (not all,  to my knowledge, but most) make their AR's in 5.56 chamberings, since .223 can safely be fired in it but not vice versa.

BUT...when manufacturers use 2 different chamberings for the same named cartridge, it does produce confusion, which does cloud the issue of selecting between the 6.5 and 6.8.

I'm sorry, but MOST people don't know the difference, and unless it is pointed out, have no idea.

Originally Posted By Grendelizor:
The technical side of this debate can't be settled until the 6.8 SPC camp decides which 6.8 chamber will be the industry standard, the SPC I, the SPC II, or the SPC III, and until they decide which cartridge performance specifications and pressures will work safely in the chosen industry-standard chamber.

I tried debating, via my infamous 6.5 Grendel charts, technical performance standards. For the 68SPC load, I choose a Silver State Armory gen. 2 factory load whose velocities were independently verified by Gary Roberts himself. "Foul!" cried the 6.8 SPC camp, "those figures are misrepresentative!" Ex-frickin'-scuse me? Let's try that again: Latest factory load from the leading 6.8 SPC ammo maker. Independent test data. Invalid? "Oh, yes, the data is invalid," said the 6.8 guys, "we can easily achieve 200-300 fps more at safe pressures with our handloads. Try stickin' that in your charts."

For any given bullet weight, I'll give the 6.8 SPC 25-75 more feet per second than the same weight bullet in 6.5 Grendel, due to bolt-thrust and piston-area issues (muzzle velocity for lighter bullets will be skewed toward the 68SPC due to piston-area, for heavier bullets it will be skewed toward 65G because of less case intrusion). Let's call it an average muzzle velocity advantage (ignoring the effects of BC down-range) of 50 fps in favor of the 68SPC.

What I will NOT give the 6.8 SPC is a 200-300 fps muzzle velocity advantage (with performance equalling the .243 Winchester per bullet weight, as I've seen claimed). As Hi-Tech-Rancher rightly points out, this is the crux of the issue and we're, apparently, at an impasse.

The only performance specifications worth debating are independently verified factory ammo. Put another way, until the industry agrees on standardized chamber and ammunition specs for the 68SPC, it's not really worth debating.

John

| 6.5 Grendel: The Tier One AR Cartridge. |

www.65grendel.com

Originally Posted By QuicksilverJPR:You could use the 6.5Grendel 90gr Speer TNT and the 6.8 SPC 85gr SSA TSX load as a comparison (roughly).  Just using muzzle velocity, the SPC load (SPCII chamber, 1:10" twist) achieves 2850fps out of a 10" barrel, whilst the Grendel achieves a  velocity of 2880fps with the 90gr Speer TNT out of a 24" barrel. The 14" barrel length difference between the two is kind of crazy, but it illustrates the point of the difference between the two loads vs. weapon barrel lengths...

Originally Posted By Grendelizor:  I can't verify why a neophyte ammo maker like Hornady, for example, is unable to get anywhere near the results of Silver State's astute application of physics.

Originally Posted By MudBug:



This is gonna get deleted, but I detected some sarcasm in his post. I think his post was a poke at the performance claims by SS with a tounge in cheek insinuation that hornady can't reproduce their results so hornady must be inexperience at ammo manuf.

Originally Posted By exhogflyer:
Very, very interesting topic this.When I first saw it I figured " Oh God, not again", as I'm sure many did.I liked what I read, the info, the opinions, even the "bickering".....seems, well, required.This is a hot subject, with many arguments made back and forth and guess what...it'll NEVER get settled..and I'm GLAD!
Why not? Because, we like choices..hell shooting is ALL about choices..IE, what length barrel, what weight bullet, what type scope, what make rifle, and so on.If we could all simply pick a "best" and get on with it we'd be bored out of our minds.So, we carefully choose, then elaborate, then justify...and it will all make sense. Ok, now to the point...
I'm no expert, but I did chose the 6.5 based on that I like to reload ( factory ammo is no concern),I enjoy shooting at longer ranges ( better bullet selection for this purpose),I like "weird" calibers ( 6.5 fits), and I don't care about hunting or shooting zombies with this round.
Works for me and the choice was that simple...