This might be a good time to do a "review of the state of the 6.8." What is my purpose? Well, there have been many changes since the first 6.8 Performance test I helped host at Wild River Ranch. I think it would be wise to help update those who have bought 6.8's and those still trying to sort out all the nuances of the newer specs like chamber, leade, and twist rates. At this point, I cannot state clearly enough that history is repeating itself.

Does everyone remember the .223 Remington, and how it later became the 5.56mm NATO? That is almost exactly what is happening with the 6.8 Remington SPC, which I now consider to be defunct. ( I define this as the market not wanting this any more, since there is a much better alternative available) What do I mean by this? I say "almost" because the 5.56 mm NATO was born out of a desire to increase velocity and the pressures necessary to produce them, when the US military adopted the .223 Remington, and then transformed it for military use. Given the longer leade of the 5.56 NATO chamber, the 5.56 mm cartridge could generate higher pressure and velocity. However, when firing this same cartridge in the slightly more snug .223 Rem chamber, pressure spikes could occur which would lead to parts failure or worse.

This is why it is generally not recommended that you fire 5.56mm NATO cartridges in .223 Remington Chambers.

And now, short of the US military adopting the 6.8 mm Rem SPC, history is repeating itself... Sort of... 2009 is very different from the 1950's and 1960's. The primary difference is that there is a huge and still-growing civilian market for AR-15 rifles, despite the near-50 year old design. Hey, the B-52 is still one of our workhorses isn't it? But, I digress....there is an ever growing demand for the rifle to produce more power, in terms of both combat effectiveness and for killing game, since so many hunters have begun using this rifle, as well. The big problem is that we have a magazine well, and mag that holds 2.30" of cartridge and that's all you get. Remember the Kohler commercial , where the lady asks the architect to "design a house around this..." and she shows him the kitchen faucet? There you have it!

In comes the 6.8 X 43 mm SPC. For now, this is what we will call the "new" cartridge. Its new chambers are currently known as "6.8 SPC II" (analogous to the 5.56 NATO) and the "6.8 DMR." (analogous to the .223 Wylde match chamber). You all know now that the original design (by Murray and Holland) was not what Remington released to the public, and it never met their claims of firing a 115 grain bullet at 2800 FPS from a 24" barrel. In fact, that misrepresentation almost, in itself, killed the whole idea. Shooters were rightly disappointed when what we got was really 110 grain bullets going around 2550 FPS.....YAWN. You should know that rifles chambered with SAAMI chamber and 1 in 10" twist could not consistently produce such a velocity with this bullet. The pressures are too high.

Then an amazing thing happened. Enterprising individuals like the proprietors of Ko-Tonics, Silver State Armory, AR Performance, Titan Armory, and others went "back to the drawing board," to create the genesis of what we have today. I like to call it the 6.8 X 43mm SPC. I hope someday we'll call it the "6.8 X 43 mm SPC NATO," but that is another story for another day. I don't think any of you can dispute that it is a clear evolution of the design, and superior to the Remington effort.

In fact, today's 6.8 X 43 mm SPC is NOT the 6.8 Remington SPC. There, I said it. Dimensionally the case is exactly the same. ONLY the chamber is different, because the first one to shoot the cartridge could not do so safely, when Remington tried to reach its velocity claim. The only "difference" one can argue is present in the "new" 6.8 X43mm SPC, is that the longer leade allows the COAL to be safely extended to 2.30". Remember that number from above?? Now, we can extend the OAL to full mag length, wringing out all the powder capacity this case can offer. The extra leade allows more powder capacity , thus more velocity at less pressure, and if we are lucky and the barrel designers are also smart enough to use thin lands, and 3, 4 or 5R, perhaps poly grooves, the pressure is even further ameliorated, and we now see velocities like the Barnes 85 grain TSX going 3100 FPS from a 16" barrel! Even better yet, the DMR chamber, designed by AR Performance, gives us Match accuracy in the 6.8. Just see my targets below and see what I mean. You can have this, too:

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THE FIRST TWO USED A COAL OF 2.30" ( not the SSA factory, which I believe is loaded to 2.26." It must accommodate the SAAMI chamber )

As we have now shown you many times, some pretty astounding velocities are possible, with this cartridge, IF the barrel specs, chamber, rifling dimensions, and twist all come together for the ultimate low-pressure environment. It is very easy for a manufacturer to select 3, 4 or 5r rifling rather than 6 groove, 1 in 10" twist with larger lands:





(Source: 6.8 Performance test and pressure trace test, executed at Wild River Ranch, February, 2008. This was a GS custom 80 grain all-copper, Moly coated, banded bullet, fired from a max test load. Average vel. for this string was lower....3360 FPS)


Now, we can take full advantage of the parent .30 Rem case's exceptionally high efficiency, and with the .277 bullets we now have on the market, we have a completely new level of performance, with higher powder charge safely driving a longer bullet with a better BC. Can there be any argument that this is a major improvement?

So, for all of you that still believe it is a "wildcat," PLEASE do some homework. The following list will now include all the manufacturers that agree with us, that the 6.8 X 43 mm SPC is not only NOT a wildcat, but that a SPC II or DMR chambered rifle is is the SAFER of the two rifles, versus the SAAMI - approved design.  If you reference the 6.8 performance test and report we posted in March of 2009, you will see that SAAMI chambers produced anywhere from 2 - 8,000 PSI more pressure for a given cartridge fired in two different barrels, when compared against one that had SPCII or DMR.

The old specs were in error, and it is now clearly established that, just as with .223 and 5.56, the longer leade chamber (and Match DMR ) are the ones appropriate for the "military pressure" 6.8 SPC cartridge. We do not know what to call the SAAMI approved- 6.8 REMINGTON SPC chamber, because it is essentially dead, as it was too short to allow for anything other than the REMINGTON load, which too, for all practical purposes, died a few years ago. We absolutely cannot explain why SAAMI continues to back the chamber which is exactly analogous to firing a 5.56 round in a .223 chamber for the 6.8 SPC. This is not something that ANY of you, as AR shooters, should have any difficulty understanding.

We also believe that SAAMI should recognize the SPC II chamber since almost all manufacturers are now making 6.8 rifles with those chambers anyway. We believe that SAAMI should issue a recommendation to manufacturers to recall all SAAMI chambered rifles so that they may very simply be reamed to the .100 freebore dimensions of the SPC II chamber. Owners may opt to personally ream their own chambers or have local 'smiths do it. We believe that getting these barrels out of circulation will allow the final evolution of the cartridge to take place.....once and for all.

These Manufacturers now offer the proper, updated specs for 6.8 SPC. Their leade / chamber can shoot the new 6.8 X 43mm SPC which is analogous to the 5.56 NATO cartridge. Many of them have opted for slower twist rates, like 1 in 11" or 1 in 12" which we endorse, though we still see some 1 in 10" twist rifles that can handle very high velocity 6.8 X 43mm loads. Choose your twist based upon bullet length, density and weight.


AR Performance

Armalite

Barrett

Bison Armory

Bushmaster  (Edit June 25, 2009.... I just received word that they have decided to go with 1:11 twist, 4 grooves and SPCII chamber....Bravo! )

Charles Daly Defense ?

CMMG

DPMS (as of 6/30/09, I confirmed that all chambers going forward will be SPC II,  bravo DPMS ! )

JTAC Supply (offers Shilen and WOA barrels)

LWRC

LOTHAR WALTHER (Making all three chambers.....However,  still providing the SAAMI chamber to some OEM's and I for one, wish they would recommend against it, or stop offering it altogether, as this perpetuates our problem.)

Noveske

MSTN  (my understanding is that they use premium Douglas blanks and the SPC II chamber, but I need confirmation from them)

Patriot Ordnance Factory

Robinson Arms

Rock River Arms

Stag

Titan Armory

White Oak Armament


Those companies below, unfortunately, inexplicably, still do not make a 6.8 SPC II or DMR chamber. This makes their rifles potentially unsafe to fire the 6.8 X 43 mm SPC (like the 5.56)  since it has something like a .223 chamber. Some even have selected twist rates as fast as 1 in 9.5 " which is suitable for .270 Winchester bullets of weights in the 130-160 grain range, and are generally not loaded in any 6.8 SPC ! We suggest that, given reasons of clarity and general safety, that you buy from the first group. If you reload or buy any factory ammo, you would not have to worry about whether your gun can shoot "military, combat, or tactical" pressure loads. You can buy anything currently loaded without having to think twice about that. If you buy one of these barrels, you will have to constantly work to find downloaded, lower velocity ammo that is on a par with the now-defunct Remington designed 6.8 SPC loads from 2003 - 2006.



Lewis Machine & Tool

Model 1 Sales

Ruger (Mini )

Remington ( only makes a bolt gun)


Note:  in no way do I want to imply that the second list of manufacturers produces sub-standard quality guns or barrels.  In fact, I own LMT, Ruger and Remington products and I find them to be high quality.  I just don't own anything in 6.8 made by them, and I won't until they make the updated spec barrels.  The fact that they are still making SAAMI chambered guns makes it difficult for ammo manufacturers to produce 6.8 X 43 mm SPC ammo which can achieve the cartridge's full potential.  That is the reason why we recommend that you buy from those using the updated specs.  When all of the guns produced will fire 6.8 X 43 mm SPC, ammo MFR's will be free of the liability that might also come from, say,  producing hot 5.56 ammo, in a market full of .223 chambered guns.  It is just that simple.

__________________

Great info and big thanks to all those doing the hard work.

Great info since I have the RRA upper. Got it in may and have found that it shoots clover leaf patterns at 150 yards with silver states ammo even if it is 1 in 10 twist.

This is great info for anyone thinking about the 6.8.

Nice job HTR. This is getting the good (accurate) info out.

good stuff

This is a great summary of today's 6.8 rifle market. I'd like to thank those companies who offer the updated specs enthusiasts have been asking for. Armalite's recent announcement of their upcoming SPC II, 4-groove, 1:11 barrels was a great surprise. Now you can see that almost all of the major AR manufacturers offer improved performance in their 6.8 products. Hopefully Bushmaster and LMT will come on board also.

The word is getting out. The 6.8 consumer is more aware of what to look for and now has more choices than ever.

If you look at the list of manufacturers offering the proper specifications, you can see that there are offerings for everyone. You have factory M4 style uppers all the way to custom precision uppers.  

so if I wanted a  "556 nato" 6.8, would 1:10 kotonics early barrel work for that?

ETA I have a line on a 16" mid-length early Ko-tonics barrel but need confirmation from you gurus that I can load some "high pressure" stuff for it.

I would advise against getting that barrel. It may have the spcII chamber, however, Kotonics did not make a 1:10 barrel. It is actually a misprint on the barrel, in reality it is a 1:9.5 twist. Don't get me wrong it is still a decent barrel accuracy wise, but you will not be able to shoot the hotter loads. I used to have the exact same barrel. I got under 1" groups at 100 yards with great consistency, but I had to download all my loads about 1 grain in order to combat high pressure signs.

I would recommend going with Bison Armory. They are more like the modern Cardinal Armory offering SS 6.8 spcII 1:11 4 groove barrel for very good prices. As of right now he has unthreaded 20" barrels in-stock for $195. He also has some custom uppers in the mid $400's to low $500 minus the bolt carrier. The mid $400 range will include everything else except for the bolt, whereas the  high $400 to low $500 range will have a bolt depending on the options. Like I said, if you only want the barrel he has the 20" in-stock, or you can get on his pre-order for either the 16" or 18" threaded barrels with an Ops-inc shelf machined on the barrel. These are $200 because of the added Ops-inc suppressor shelf, and I believe they require a $100 down payment. I highly recommend these barrels as an economical option. I have one of his 18" threaded uppers from the last shipment, and I can easily get 1/2" or better groups with Speer TNT's.

You should go check out his website at www.bisonarmory.com

+1  

Hogzilla has hit the nail on the head.  ER Shaw made all the Ko-Tonics, and then later Cardinal Armory barrels.  Tim Hicks did not revamp the barrels to the "new spec" (SPC II chamber )  until the 1 in 11" twist, 4 groove barrel was released.  If you have the 1:10 stamped barrel, then it will not handle the 6.8 X 43mm loads well.  That barrel is the exact same thing as a Model 1 sales barrel, also made by ER Shaw with SAAMI chamber, 1:9.5" twist, 6 grooves.  This is the worst possible combination for higher pressure ammo.

The barrel you're considering would work well for one thing: shooting subsonic 130 and 150 grain bullets, and possibly cycling the action since it generates so much pressure.  The 1 in 9.5" twist will stabilize the ridiculously long 150 grainers, and if you use 7.5-8 grains  of Trail Boss, you'll get a wonderful sub out of it.

For cycling the action, you might need to use Clays or Unique.

What about DPMS?

Did Randy decide to drop the 6.8 after all?

DPMS needs to be verified. Know anyone there you could call?

We also heard DPMS was out, then a 68forums member received an email from DPMS stating they were going to SPC II.  So HTR can always add them to the list once we have verification.  

I think the same meber has one on order and has verified through e-mail but it could be the last one or they could be continuing with the correct specs.

Being only a potential 6.8 buyer right now, how would I know I was getting the correct barrel? Will the barrels be stamped in a way that would let us know it is the x43 or type II chamber and barrel? Will simplye sticking to the lower list of makers be insurance enought?

What about the Recon barrels from Denny at Global Tactical?  Or would these fall under the WOA barrels?

They should be stamped the same as a 5.56 barrel ie.. 6.8 1:11  spcII or something like that.

tag.

tagged to read again later when I have time.


edit: question for the OP:

You say 'we' several times in your post.

Who is 'we'?

What group do you represent here?

I knew that would come up.

"We" are the people that have taken the cartridge that Remington could not deliver, and made it what they promised.  We are the manufacturers that invented the DMR chamber (Harrison Beene of AR Performance) and the SPC II chambers (Tim Hicks of Cardinal Armory is generally credited with this) .  We are guys like Art Kalwas at Silver State Armory, who knows just a little bit about loading ammo.  We are guys lke me, who have shot hundreds of animals with every rendition of the 6.8 SPC, and who have loaded everything from 80 grain GS's at 3360 FPS, to the 1.19" long  110 Barnes TTSX's to subsonic 130 grain Ballistic silvertips.  Otherwise, the list is far too long to enumerate.  

Most of us have never been compensated a penny for our work.  Others, whom are in the business to sell rifles now, did their work long before they benefitted financially from their "better spec" products.  It was only after Cardinal Armory went under that ARP, Bison  and Titan Armory decided, in such an incredible uncertain time politically, to get into the gun business.  My hat is off to them.  They did what they did, because they knew this platform would die if left to those who didn't know much about it, or didn't really care, were the only ones that sold the product to unsuspecting buyers.  

Ok, that makes sense now.


What ever happened to Tim Hicks? He's one of the most upstanding folks I've ever done business with, and I hated to see him close his shop.

We did not list a manufacturer in the first group unless we were sure that they were already selling SPC II or DMR chambered barrels now.  That is why you don't see DPMS.  We are not yet sure.  My recommendation is that, until you are 100% sure they make their barrels in SPCII or DMR, I would steer clear.  Feel free to call them, ask them, and if they say "no,"  then simply say   "...sorry guys, until you do, I will buy the barrel that allows me to safely shoot the faster ammo."

As for the second list, I am not bashing them.  I am simply telling you that you should write them, call them suggest to them that they need to get up to speed and produce barrels with the updated chambers.  Tell them that you will take your business to those who make the updated chamber.....until they do.

As long as these SAAMI chambered guns are on the market, the ammo will be held back to the lame velocities that was given us after Remington discovered that their primers were leaking, the leade was too short and the powder they chose initially was too temperature sensitive.

We need to get rid of the SAAMI chamber, once and for all.  It is ridiculously easy to ream it out to SPC II.

These are WOA, they are now all SPCII, and 11 twist, and thus, GTG.  I have one and find it to be a fantastic barrel.  I love mine.  It handles everything I throw at it.

One can quibble over the meaning of "wildcat", but your whole post is an argument that 6.8 IS a wildcat, or in development, call it what you will.  As you admit, one can still not go to a local gunshop and pick up a rifle that is not safe with all factory ammo.  SAMMI has yet to recognize your work (SPEC II, twists, etc.).  What ever you call that, it is not a stable spec that is going to storm the marketplace IMO.

Also it would be wise for anyone reading your post to recognize not only the selfless work you guys have done, but also the fact that the "we" referred to above do have much personal, emotional and financial investment in the success of 6.8 (ver. X).  A "state of" something is best left to a neutral third party, or at least someone without a direct investment in the thing being reported on.  I commend you for being open and honest about your commitments, so that folks reading this 'report' will realize and consider the source.




The above is an excellent reason why one must be consider the source with information coming from the above mentioned “we”.  The temptation for group self protection is very strong.  My personal experience is that the “we” have directly protected one company by not allowing honest reporting defects over time and locking any thread and discussion that is not flattering to said company over at 68forums. This needs to be considered when looking at any list of companies (whether approved of or not).  Caveat emptor...

EDITED, KEEP PERSONAL ATTACKS OUT OF TECH, NEXT ONE IS A WARNING AND REC FOR LOCK OUT OF TECH ~ Cold

Edited, personal attack removed from above quoted material ~Cold

I apologize if you thought this was a personal attack, not my intent.  

But back to technical discussion....

http://68forums.com/forums/showthread.php?t=6713

you really have to work hard to get banned on that forum

Bushmaster confirmed via email from their Tech Support that they are going to SPC II and 1:11 twist barrels over the next few months. So if you want a BM 6.8 it's worth a little wait to make sure you get the better barrel specs. Armalite's new barrels should be out soon also.

Off topic  next one is a warning and my rec to have you LOCKED OUT OF TECH ~ Cold

Decided to remove since it is off topic and pointless.

It's still a wildcat.

One that is gaining ground and making huge leaps in both performance and adaption, but until there is a change in the SAAMI spec to meet the new specs, or the specs as they are now gain standardization in the market it's still a wildcat.


That's not to take away from all the work that has been done, and the huge performance increases. I'm actually kind of in awe at what you guys have done with this.

1) For the record:  I have never sold one single penny's worth of 6.8 ammo, or  products such as barrels, accessories, etc.  I am doing this because I am a dedicated scientist and this was a challenge.  I also happen to find the 6.8 has forever, dramatically changed my use of the AR-15 as a hunting weapon, especially well-suited to defusing the "pig bomb" in south Texas where I ranch and hope to help my neighbors protect their crops and livelihood.  If I can help others to learn this wonderful new thing....I have done something positive.  If I can help the US military find a better cartridge to kill the P'sOS, like those who knocked down the World Trade Center buildings, I have done something positive.  This has nothing to do whatsoever with monetary gain or a bias toward anything, any company or entity.   I am the first to tell people to take what I say like everything else they read on the internet....with a grain of salt.  Your opinion might be more helpful....I don't know....I haven't seen your work.

2) Call this thing whatever you want.  I don't think 90% of the people making the guns that fire this cartridge care if you call it a wildcat.  They know what we know.  Without changing ONE SINGLE DIMENSION OF THE PARENT CASE, this cartridge now performs the way we were promised it could from the very start.  You just need a little different chamber to shoot it.  That makes it a  Wildcat???  Whatever.

But thank you anyway for your compliment, Mudbug.  I will take one from you any way I can get it.  Discerning skeptics like you don't bother me at all.  A jaundiced eye can be a good thing, so please continue to give me your input, as long as it is constructive....I welcome it.

KEEP PERSONAL ATTACKS OUT OF TECH, next one is a warning and my rec to have you LOCKED OUT OF TECH ~ Cold

I'm familiar with all of that, and agree - but where is he now?

It's a shame he's not working for someone in the industry now. Tim's a stand-up guy.

Okay.... so now with BM's announcement they're going to SPC II, that pretty much means the ENTIRE 6.8 industry has gone to improved chambers like the SPC II, and DMR. Almost all of the same companies have gone to slower twists, and the rest are looking into other twists.  But it's still a wildcat.....  That's interesting, the entire 6.8 firearms industry (all the major AR manufacturers) is producing the 6.8 Wildcat.

Sounds like SAAMI is slow or incompetent in the matter, not the rest of the industry. So you're saying Model 1 Sales is the only SAAMI compliant 6.8 manufacturer? Who'da thunk?

one time a mechanic said to me I have  been doing this for 30 years kid and who are you to tell me how to do it, I said well old man its time to learn how to do it right and besides that I am your boss.
things change Saami

tag

Is it possible to have a 6.8 SPC SAAMI spec barrel 'rechambered' for 6.8 SPC II?

If so, who does this?

Yes.... if you go over to the 68forums, Paulo (a member) has a sticky where they are doing 6.8 chamber reamings for a nominal fee.
OR... you can get on their "reamer list" and a member will ship you the reamer and you can ream your own SAAMI chamber to SPCII.
Supposedly, the reaming job is idiot-proof, needs no tools other than your hand, the barrel (still in the upper is OK), the reamer and
some oil.... takes 5 minutes.

I should be getting a reamer in anyday now... for my two barrels. I'm pretty sure one of mine is SAAMI and the other I'm not sure about.

-ZA

Oh.....

BTW, awesome write up HTR!

-ZA

Great write up and thanks for all you have done!

I have a stripped lower just waiting for a 6.8 SBR upper.

HTR donates his ranch for tests no?  I believe he put people up, donated equipment, etc.  Correct me if I am wrong but he is intimately involved in the promotion of 6.8 going back some time.  A 3rd party would be a someone who has no dog in the fight of 6.8 "old" vs. "new", 6.8 vs. 6.5, etc.  Perhaps a respected gun writer who owns neither and is not trying to correct or modify either & is not interested in promoting either.

For the record, I will likely keep my 6.8 barrel/bolt.  I do not drink the 6.8 kool-aid however, and I am not a promoter.



A recall for doing things to the recognized industry standard?  One would normally say such things to contend that things are in "development" or dare I say, "wildcat".

Again I commend HTR for being upfront with his involvement.  "If I can help others to learn this wonderful new thing" is indicative of real personal involvement that goes deeper than mere financial gain.  Such emotional and personal commitments are far deeper and important to folks than the financial.  It is also anything but neutral...

So, the timing on this discussion is great for me.  I just received my 6.8 upper from Stag that I ordered last January.  I felt like a kid waiting for my cereal boxtops to turn into a decoder ring.   (I know, I know...PICs on the way.)

Now I'm wondering if anyone makes a scope with 6.8 bullet drop compensation.

Here's one for the .223, for example:   BSA scope

does anyone know of a good, reasonably priced scope for 6.8 SPC?

That's great that Bushmaster is switching to the improved specs of the round. Has there been any sort of notification if LMT will be going to the SpcII and 1:11 or 12 twist?

Hard not to notice how hard you guys have worked and the quality of the result.





When this whole silliness between the 6.8 and the other thing started, the fact that the 6.8 had a SAAMI cert was used as proof that it was the more legitimate round, now it's being argued that it's just been an albatross around the 6.8's neck.








I'm betting it's more a difference on our definition of a Wildcat, and just so you know I see the other 6 something round as several rungs below this one on the ladder.

I ditto this question.  I recall reading that a scope for .308 is "good enough" but not sure.  I know a scope for 7.62x39 certainly would not work...

I know that you said in a reasonable price range (and this is waay out of mine), but Trijicon makes an ACOG equiped with a 6.8 bullet drop compensator.

Hope that helps.