Today's State of the Art in 6.8 X 43 mm SPC

HTR707

Sergeant
Commercial Supporter
Full Member
Minuteman
May 12, 2008
228
0
Rockport, TX
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,<span style="font-style: italic">I cannot state clearly enough that history is repeating itself.</span>

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:

ARP1.jpg


DSCF7003.jpg


ARP4.jpg



<span style="font-weight: bold">THE FIRST TWO USED A COAL OF 2.30" </span>( 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:


DSCF1034.jpg



<span style="font-weight: bold">(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)</span>


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 and DMR chambers, 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

JTAC Supply (offers Shilen and WOA barrels)

LWRC

Noveske

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) in your gun (which 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.


<span style="text-decoration: line-through">Bushmaster</span>

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, Remington and Bushmaster 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.

__________________
AKA hi-tech-rancher
 

jamesb74

Private
Full Member
Minuteman
Jan 19, 2009
98
0
Texas
Re: Today's State of the Art in 6.8 X 43 mm SPC

Nice write up HTR It is amazing how far this caliber has come.
 

sinister

Gunny Sergeant
Full Member
Minuteman
Apr 16, 2002
2,164
883
College Station, Texas
Re: Today's State of the Art in 6.8 X 43 mm SPC

It remains a wildcat, ergo no standard.

The Sporting Arms and Ammunition Manufacturer's Institute simply acts as the repository for the standard submitted to them by the manufacturers. Their interests are safety and compatibility standardization. Unless an established ammo manufacturer insists on changing standard there's no reason to change.

Gun manufacturers are in the "Grey area" and open themselves to civil suits if anything should ever go wrong with an item they produce and sell with their marque.

There is no MILSPEC and no other published industry standard exists.

It takes one company to be the standard-bearer. "Someone" convinced Remington if they produced the round commercially the US military would instantly accept and buy it. They got stuck. You can probably understand their reticence -- if it doesn't make money it costs money. Businesses are not in the business to lose money.

The 6.5-08 is now the 260 Remington. There are two standards for 338 Lapua (SAAMI and European). There are .223 and 5.56 loadings, and 223, 5.56, National Match, Infantry Trophy, and Wylde chamberings for ARs. There are 308 Win, 7.62, and Palma chambers.

If you expect to see off-the-shelf ammo someone has to put their company's name on it.
 

Hoser

Ninja
Full Member
Minuteman
Apr 12, 2005
1,592
668
111
East Africa
Re: Today's State of the Art in 6.8 X 43 mm SPC

Is AR Performance still even around?

He quit posting here a long time ago.
 

Niles Coyote

Gunny Sergeant
Full Member
Minuteman
  • Aug 13, 2007
    4,357
    964
    South West, MI
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    Wasn't the hole idea of the spc to make a more effective cartridge at the extreme end of the 5.56's range envolope for A-stan, 500 yards on out in a m-16??? Maybe Im missing something, but I dont see much difference in a light weight 6.8 bullet @ 3100 to a mid weight 5.56 going 3100+. Its still a short range weapon...
     

    paulo_santos

    Sergeant
    Full Member
    Minuteman
    Jan 4, 2006
    491
    0
    47
    NJ
    www.spdcrossfit.com
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Niles Coyote</div><div class="ubbcode-body">Wasn't the hole idea of the spc to make a more effective cartridge at the extreme end of the 5.56's range envolope for A-stan, 500 yards on out in a m-16??? Maybe Im missing something, but I dont see much difference in a light weight 6.8 bullet @ 3100 to a mid weight 5.56 going 3100+. Its still a short range weapon... </div></div>

    In soft tissue they are similar, but the 6.8SPC is still better because of the lower fragment threshold. Where the SPC really beats the 5.56 is barrier penetration. The SPC is a short-Medium Range Caliber.
     

    paulo_santos

    Sergeant
    Full Member
    Minuteman
    Jan 4, 2006
    491
    0
    47
    NJ
    www.spdcrossfit.com
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: sinister</div><div class="ubbcode-body">It remains a wildcat, ergo no standard.

    The Sporting Arms and Ammunition Manufacturer's Institute simply acts as the repository for the standard submitted to them by the manufacturers. Their interests are safety and compatibility standardization. Unless an established ammo manufacturer insists on changing standard there's no reason to change.

    Gun manufacturers are in the "Grey area" and open themselves to civil suits if anything should ever go wrong with an item they produce and sell with their marque.

    There is no MILSPEC and no other published industry standard exists.

    It takes one company to be the standard-bearer. "Someone" convinced Remington if they produced the round commercially the US military would instantly accept and buy it. They got stuck. You can probably understand their reticence -- if it doesn't make money it costs money. Businesses are not in the business to lose money.

    The 6.5-08 is now the 260 Remington. There are two standards for 338 Lapua (SAAMI and European). There are .223 and 5.56 loadings, and 223, 5.56, National Match, Infantry Trophy, and Wylde chamberings for ARs. There are 308 Win, 7.62, and Palma chambers.

    If you expect to see off-the-shelf ammo someone has to put their company's name on it. </div></div>

    Look at the list of manufacturers already using the SPCII Chamber. Only LMT and Model 1 remain with the SAAMI Chamber. The SAAMI Chamber submitted was wrong. Whether it was a mistake or on purpose is another story. The only difference between the SAAMI and SPCII Chamber s the longer .050" throat. Everything else is the same. You can still shoot all of the available factory ammo in a SAAMI or SPCII Chamber. Just like you can shoot any of the .223 ammo in a .223 or 5.56 Chamber. I don't consider the SPC a Wildcat. There is plenty of factory ammo available for it. Even if it is considered a Wildcat, who cares. It was initially designed by the Military for the Military, but they have decided not to use it. That is their loss. It is turned out to be a great Hunting/LE/SHTF Round.
     

    silver78

    Sergeant
    Full Member
    Minuteman
    Nov 2, 2004
    121
    0
    61
    MD
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    Glad I waited and bought an upper from Hollinger. I'm surprised that LMT has not come up to speed on this. No surprise that Ruger is still behind the curve. I do have a question. On your "good" barrel list, which companies have never produced an old spec ("bad") barrel. If we know that information then someone can buy that brand with full confidence. In some ways the "good" list can get you in more problems than the "bad" one. Everyone knows to avoid the "bad" list. But if someone who is now on the "good" list built some older "bad" barrels we would need to know this in case we end up buying a used barrel or upper.

    PS - I am not complaining. I greatly apreciate what you have done in pulling together all this information. Thanks for the list this is way over the top.
     

    paulo_santos

    Sergeant
    Full Member
    Minuteman
    Jan 4, 2006
    491
    0
    47
    NJ
    www.spdcrossfit.com
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: silver78</div><div class="ubbcode-body">Glad I waited and bought an upper from Hollinger. I'm surprised that LMT has not come up to speed on this. No surprise that Ruger is still behind the curve. I do have a question. On your "good" barrel list, which companies have never produced an old spec ("bad") barrel. If we know that information then someone can buy that brand with full confidence. In some ways the "good" list can get you in more problems than the "bad" one. Everyone knows to avoid the "bad" list. But if someone who is now on the "good" list built some older "bad" barrels we would need to know this in case we end up buying a used barrel or upper.

    PS - I am not complaining. I greatly apreciate what you have done in pulling together all this information. Thanks for the list this is way over the top. </div></div>

    6.8SPC Chart.
     

    HTR707

    Sergeant
    Commercial Supporter
    Full Member
    Minuteman
    May 12, 2008
    228
    0
    Rockport, TX
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Niles Coyote</div><div class="ubbcode-body">Wasn't the hole idea of the spc to make a more effective cartridge at the extreme end of the 5.56's range envolope for A-stan, 500 yards on out in a m-16??? Maybe Im missing something, but <span style="color: #FF0000">I dont see much difference in a light weight 6.8 bullet @ 3100 to a mid weight 5.56 going 3100+. Its still a short range weapon... </div></div></span>

    <span style="font-weight: bold">You mischaracterized the real difference</span>:

    Shooting a 77 gain SMK at 2600 FPS is not in the same league as an 85 grain Barnes TSX going 3150 FPS, is it?

    I don't think 5.56 and 6.8 are that close at all, anymore. You have to remember that, in order to reach velocities of 3100 FPS in 5.56, you will be shooting 55 or 62 grain bullets <span style="font-weight: bold">in 20" barrels</span>. You are not going to move a 77 grain bullet that fast in the 5.56, with a barrel any shorter than 22". The .223 case is very inefficient, therefore creates much more blast, flash and heat for the velocity you get with its bullet.

    The 6.8 SPC can generate that same velocity in a barrel as short as 12 inches, and for sure 14.5," such as the length found on the M4. Huge difference.

    Higher bullet weight, 550 FPS faster, in a barrel of the same length, OR same velocity with heavier bullet in a barrel 8 inches shorter.

    Even without considering terminal performance (which happens to be quite superior in the 6.8) this is a HUGE difference.



     

    HTR707

    Sergeant
    Commercial Supporter
    Full Member
    Minuteman
    May 12, 2008
    228
    0
    Rockport, TX
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    silver78 said:
    Glad I waited and bought an upper from Hollinger. I'm surprised that LMT has not come up to speed on this. No surprise that Ruger is still behind the curve. I do have a question. <span style="color: #FF0000">On your "good" barrel list, which companies have never produced an old spec ("bad") barrel.</span> If we know that information then someone can buy that brand with full confidence. In some ways the "good" list can get you in more problems than the "bad" one. Everyone knows to avoid the "bad" list. But if someone who is now on the "good" list built some older "bad" barrels we would need to know this in case we end up buying a used barrel or upper.



    Actually, that is a great question:

    Here is my best answer:

    1) AR Performance. They have never made anything other than the 11, or 12 twist SPC II or DMR chambered barrels. My 12 twist, 3 groove, DMR, 20" stainless barrel is the one which produced the excellent groups you see above in the pictures.

    2) Bison Armory: these guys picked up where Cardinal Armory left off. They took Tim Hicks' design and asked ER Shaw to continue making the barrels as Tim originally specified. That is, 11 twist, 4 groove, SPC II. At this time, I believe they are only available in SPR profile stainless.

    3) Titan Armory

    4) WOA: Despite the fact that Holliger used the SAAMI chamber in the beginning, we shot some pretty hot loads in these barrels during our pressure test and they were on a par with the Cardinal Armory barrels which used the SPC II chamber. Our best guess was that 1) they have 1 in 11" twist, and 6 groove rifling, and no chrome (obviously) 2) he knew well enough to make the lands of such dimension to reduce pressure in that manner. To this day, they are the only SAAMI chambered barrels we have ever seen that handles almost any 6.8 X 43 mm load. Notably, WOA has since changed all their barrels to the SPC II chamber, and accuracy has not suffered one bit.

    It is very important to note that even if you bought any of these barrels from any manufacturer, converting the SAAMI to SPC II chamber is ridiculously easy, by reaming out to the extra freebore, then equaling .100" which is .050" greater than the SAAMI.
     

    paulo_santos

    Sergeant
    Full Member
    Minuteman
    Jan 4, 2006
    491
    0
    47
    NJ
    www.spdcrossfit.com
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    I forgot to add:

    For anyone that thinks that the SPC isn't a good hunting round, the OP of this thread, HTR, has his own ranch where he has shot a ton of hogs and deer with it. HTR started this thread here and on other boards to inform guys who are interested in the SPC. The SPC isn't a Sniper Round and never will be. It is however, a great 0-300 yard hunting round. It obviously isn't for everyone, just like the .308 isn't for everyone.

    If anyone would like some info on it, please ask or stop by www.68forums.com. We are not here to shove this round down people's throat. We are just trying to pass on the information. I'm on my 6th barrel now (3 16", 1 20", 2 14" barrels.), and I have tested nearly every bullet/powder combo in each one.
     

    medicjim

    Sergeant
    Full Member
    Minuteman
    Jun 24, 2002
    149
    2
    New Jersey, USA
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Niles Coyote</div><div class="ubbcode-body">Wasn't the hole idea of the spc to make a more effective cartridge at the extreme end of the 5.56's range envolope for A-stan, 500 yards on out in a m-16??? </div></div>

    NO. The objective appears to have been to come up with a more lethal round, not a longer reaching round. A premium loading in .308 would outperform both rounds at range.

    Having treated patients with .223 injuries, I cannot fathom how anything more lethal is required. I suspect the next change in issue long arm ammunition will be driven by an enemy equipped with body armor.

     

    HTR707

    Sergeant
    Commercial Supporter
    Full Member
    Minuteman
    May 12, 2008
    228
    0
    Rockport, TX
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: medicjim</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Niles Coyote</div><div class="ubbcode-body">Wasn't the hole idea of the spc to make a more effective cartridge at the extreme end of the 5.56's range envolope for A-stan, 500 yards on out in a m-16??? </div></div>

    NO. The objective appears to have been to come up with a more lethal round, not a longer reaching round. A premium loading in .308 would outperform both rounds at range.

    Having treated patients with .223 injuries, I cannot fathom how anything more lethal is required. I suspect the next change in issue long arm ammunition will be driven by an enemy equipped with body armor.

    </div></div>


    You have all heard that the 5.56mm M855, given the shorter barrel lengths used by some troops such as the 14.5" M4, tends to make pencil wounds, as it does not reach adequate frag velocity.

    I don't ever want to get hit with it, but I will take a 6.8 over it any day of the week.

    The 6.8 achieves relatively high velocity with such short barrels, that the bullets are able to fragment or deform even when fired from 10.5, 12 or 14 inches. This, combined with the excellent frag properties of the 100, 105 and 110 grain cannelured OTM's being tested, along with the Barnes TSX, leaves very little to be desired for short to medium range combat applications. These also defeat barriers much better than does 5.56mm.

    As Paulosanots mentioned, I have killed hundreds of hogs with the 6.8, and I can tell you with no reservation, that it results in FAR more one shot knockodowns than the 5.56 ever did. The most amazing thing to see, is when an 85 grain TSX traverses the entire animal from end to end, lengthwise, and comes out the other end. Very impressive.

    Here's another huge hog, killed by a client, with my 20 inch 12 twist, 3 groove...one round went in just in front of the shoulder on the right, and it exited behind the left kidney, the other was a through and through shot as a follow up. Both 85 grain TSX's (going 3200 FPS ) exited.....it was a DRT:


    Johnspig.jpg
     

    1911nbmore

    Private
    Full Member
    Minuteman
    Jun 2, 2009
    84
    0
    51
    Phoenix, Az
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    HTR707 What are your thoughts on the Precision Reflex Inc Barrels? I didnt see them listed.
     

    medicjim

    Sergeant
    Full Member
    Minuteman
    Jun 24, 2002
    149
    2
    New Jersey, USA
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    <span style="text-decoration: underline">Practical upsides of 6.8</span>

    -Better barrier penetration

    <span style="text-decoration: underline">Downsides</span>

    -Heavier, bulkier ammo means you carry less (think the rangers in Somolia would have been OK with this?)

    -Fewer rounds per mag

    -Greater recoil impulse means longer recovery time for a second aimed shot

    -new ammunition type to field, do we inventory both 5.56 and 6.8? If no, what do we do with the SAW?

    -reliability is going to be an issue at first...it always is whenever you scale up a weapon with a new caliber projectile.



    <span style="text-decoration: underline">In my opinion, the following arguements are simply invalid...</span>


    -The current Nato M855 round doesn't fragment as easily as earlier 55 gr projectile. The problem is solved with Mk262, it does not warrant an entirely new platform.

    -Lethality of 5.56 is not adequate on humans. This statement simply doesn't hold up when evaluated against the facts on the ground. But then, who cares about facts.


    Now, we can talk about what would be the ideal service rifle of the future...and we can look at how something like the 6.8 would be good for combat in urban terrain where the structures are predominantly made of masonry type materials....but it would be academic, because the 6.8 has already been ruled out as a replacement for 5.56.





     

    paulo_santos

    Sergeant
    Full Member
    Minuteman
    Jan 4, 2006
    491
    0
    47
    NJ
    www.spdcrossfit.com
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: medicjim</div><div class="ubbcode-body"><span style="text-decoration: underline">Practical upsides of 6.8</span>

    -Better barrier penetration
    <span style="color: #FF0000">And better against soft tissue.</span>

    <span style="text-decoration: underline">Downsides</span>

    -Heavier, bulkier ammo means you carry less (think the rangers in Somolia would have been OK with this?)
    <span style="color: #CC0000">I think they would have given a left nut to have the 6.8SPC. I know I would have. YOu can't have your cake and eat it too. Sure it is heavier, but what do you expect?</span>

    -Fewer rounds per mag
    <span style="color: #FF0000">USGI Mags hold 30 rounds. Barrett Mags hold 30 Rounds.</span>

    -Greater recoil impulse means longer recovery time for a second aimed shot
    <span style="color: #FF0000">A properly set-up 6.8SPC is very similar to the 5.56. There was an independent test conducted that proved it. DocGKR actually posted the times and the 6.8SPC was actually a fraction of a second faster in CQB drills. I know you are going to say I'm full of shit, but facts are facts.</span>

    -new ammunition type to field, do we inventory both 5.56 and 6.8? If no, what do we do with the SAW?
    <span style="color: #FF0000">The 6.8SPC works in the SAW.</span>

    -reliability is going to be an issue at first...it always is whenever you scale up a weapon with a new caliber projectile.
    <span style="color: #FF0000">I think it has been out a while now that most of the kinks have been worked out. The only thing I would like to see are more magazine choices.</span>


    <span style="text-decoration: underline">In my opinion, the following arguements are simply invalid...</span>


    -The current Nato M855 round doesn't fragment as easily as earlier 55 gr projectile. The problem is solved with Mk262, it does not warrant an entirely new platform.
    <span style="color: #FF0000">It is great on soft targets, but it still sucks against barriers. The new Brown tip ammo is a much better choice over the MK262.</span>

    -Lethality of 5.56 is not adequate on humans. This statement simply doesn't hold up when evaluated against the facts on the ground. But then, who cares about facts.
    <span style="color: #FF0000">It depends on what ammo is used. The Military FMJ ammo obviously has some issues or else the 6.8SPC would have never been created. For LE use, the reports are good because most LE agencies use much better ammo instead of the M855.</span>

    Now, we can talk about what would be the ideal service rifle of the future...and we can look at how something like the 6.8 would be good for combat in urban terrain where the structures are predominantly made of masonry type materials....but it would be academic, because the 6.8 has already been ruled out as a replacement for 5.56.
    <span style="color: #FF0000">And that is their loss. We have no control what the Military does, nor do we care at this point. The Military has shown over and over that they are going to pick whatever they want, even if it is the wrong choice. Sure, I'd be happy for our troops, but most of the people buying the 6.8SPC are hunters and LE officers who want a better round. </span>
    </div></div>
     

    paulo_santos

    Sergeant
    Full Member
    Minuteman
    Jan 4, 2006
    491
    0
    47
    NJ
    www.spdcrossfit.com
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 1911nbmore</div><div class="ubbcode-body">HTR707 What are your thoughts on the Precision Reflex Inc Barrels? I didnt see them listed. </div></div>

    They are super accurate barrels that can handle all of the hotter loads even though they are 1:10"/6-Groove/Murray Chamber. These barrels were the original SPC barrel and they have the original chamber, which was correct. The Murray Chamber is nearly identical to the SPCII Chamber.
     

    medicjim

    Sergeant
    Full Member
    Minuteman
    Jun 24, 2002
    149
    2
    New Jersey, USA
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: paulosantos</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: medicjim</div><div class="ubbcode-body"><span style="text-decoration: underline">Practical upsides of 6.8</span>

    <span style="text-decoration: underline">Downsides</span>

    -Heavier, bulkier ammo means you carry less (think the rangers in Somolia would have been OK with this?)
    <span style="color: #CC0000">I think they would have given a left nut to have the 6.8SPC. I know I would have. YOu can't have your cake and eat it too. Sure it is heavier, but what do you expect?</span>

    </div></div> </div></div>


    With 20% less ammo, they would have been throwing rocks
     

    medicjim

    Sergeant
    Full Member
    Minuteman
    Jun 24, 2002
    149
    2
    New Jersey, USA
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: paulosantos</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: medicjim</div><div class="ubbcode-body">

    <span style="text-decoration: underline">Downsides</span>


    -Greater recoil impulse means longer recovery time for a second aimed shot
    <span style="color: #FF0000">A properly set-up 6.8SPC is very similar to the 5.56. There was an independent test conducted that proved it. DocGKR actually posted the times and the 6.8SPC was actually a fraction of a second faster in CQB drills. I know you are going to say I'm full of shit, but facts are facts.</span>

    </div></div> </div></div>

    I'm not going to say you are full of shit, but I am going to suggest that perhaps the reason you believe this has more to do with Bias than Fact. The 6.8 ejects greater mass in both bullet and gasses, which means it will have a greater gross recoil, if the weapon systems are the same, it should have greater NET recoil. That's basic science. If you make claims contrary to established science, you need to come up with some compelling reason why we should believe the world is flat.

     

    paulo_santos

    Sergeant
    Full Member
    Minuteman
    Jan 4, 2006
    491
    0
    47
    NJ
    www.spdcrossfit.com
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: medicjim</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: paulosantos</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: medicjim</div><div class="ubbcode-body">

    <span style="text-decoration: underline">Downsides</span>


    -Greater recoil impulse means longer recovery time for a second aimed shot
    <span style="color: #FF0000">A properly set-up 6.8SPC is very similar to the 5.56. There was an independent test conducted that proved it. DocGKR actually posted the times and the 6.8SPC was actually a fraction of a second faster in CQB drills. I know you are going to say I'm full of shit, but facts are facts.</span>

    </div></div> </div></div>

    I'm not going to say you are full of shit, but I am going to suggest that perhaps the reason you believe this has more to do with Bias than Fact. The 6.8 ejects greater mass in both bullet and gasses, which means it will have a greater gross recoil, if the weapon systems are the same, it should have greater NET recoil. That's basic science. If you make claims contrary to established science, you need to come up with some compelling reason why we should believe the world is flat.

    </div></div>

    The test was conducted and the guys testing didn't know what they were shooting. If you think the test was biased, then we are just going to go back and forth all day long. The test was not biased.

    The reason that the SPC has similar recoil to the 5.56 is that the SPC uses faster powders. The 5.56 uses powders such as TAC, H4895, Varget, BLC-2, while the SPC uses powders such as H4198, H322, RE7, RE10X, X-Terminator.

    Anytime you want to go to the range, I'll prove it to you, even with my over-gassed LMT barrel.
     

    paulo_santos

    Sergeant
    Full Member
    Minuteman
    Jan 4, 2006
    491
    0
    47
    NJ
    www.spdcrossfit.com
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: medicjim</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: paulosantos</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: medicjim</div><div class="ubbcode-body"><span style="text-decoration: underline">Practical upsides of 6.8</span>

    <span style="text-decoration: underline">Downsides</span>

    -Heavier, bulkier ammo means you carry less (think the rangers in Somolia would have been OK with this?)
    <span style="color: #CC0000">I think they would have given a left nut to have the 6.8SPC. I know I would have. YOu can't have your cake and eat it too. Sure it is heavier, but what do you expect?</span>

    </div></div> </div></div>


    With 20% less ammo, they would have been throwing rocks </div></div>

    How woud they have 20% less ammo? Same magazine capacity. Sure it is a little heavier, but not like a .308.

    <span style="font-weight: bold">Either way, you win. The 6.8SPC just sucks ass and it is good for nothing.</span>
    tired.gif
    shocked.gif
    cool.gif
     

    paulo_santos

    Sergeant
    Full Member
    Minuteman
    Jan 4, 2006
    491
    0
    47
    NJ
    www.spdcrossfit.com
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    Chris, I told you that you were just wasting your time posting it here. I think you'd have better luck posting it on the Grendel Forum.
    laugh.gif
    laugh.gif
    laugh.gif
     

    Mac679

    Private
    Full Member
    Minuteman
    Nov 8, 2008
    60
    30
    CONUS
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: medicjim</div><div class="ubbcode-body">


    <span style="text-decoration: underline">Downsides</span>

    -Heavier, bulkier ammo means you carry less (think the rangers in Somolia would have been OK with this?)

    <span style="text-decoration: underline">In my opinion, the following arguements are simply invalid...</span>


    -The current Nato M855 round doesn't fragment as easily as earlier 55 gr projectile. The problem is solved with Mk262, it does not warrant an entirely new platform.

    -Lethality of 5.56 is not adequate on humans. This statement simply doesn't hold up when evaluated against the facts on the ground. But then, who cares about facts.
    </div></div>

    Why don't you ask some of the Operators that were there? Paul Howe has been quoted a few times saying he would have prefered to have had a round with better terminal performance than the M855 round (which was noted as "zipping right through"). It's mentioned in the book, it's a deleted scene in the movie. Something to do with unarmored Somalis high on Khat getting shot by a round designed to penetrate an East German steel helmet at 600m.
    As for NATO M855...what is NATO M855? The US uses M855, the Brits use L2A2 (which is made to a different spec and lower velocity, burns dirtier, etc.). The SS109 type pentetrator bullet and that they're both 5.56NATO is the only consistency. M855 is US ammo.
    As for 5.56 lethality, I'm pretty sure those who conduct ballistics testing have better insight into the just straight up raw numbers than most of us (aka ask DR. Gary K. Roberts-you can find the test results between 5.56 and 6.8 online). As for facts on the ground, where did 6.8SPC originate? 5th SFG(A) with the assistance of the AMU, if my memory serves me correctly. Doc Roberts has made more than a few notes in regards to the inconsistent performance between lots of M855-some lots have great terminal performance, some have poor terminal performance.

    And the recoil difference between 5.56 and 6.8 ain't that much, and the 6.8 I've shot was the 110gr SMK combat loads from SSA, not SAAMI spec stuff.

    Just some food for thought.
     

    HTR707

    Sergeant
    Commercial Supporter
    Full Member
    Minuteman
    May 12, 2008
    228
    0
    Rockport, TX
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: medicjim</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: paulosantos</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: medicjim</div><div class="ubbcode-body">

    <span style="text-decoration: underline">Downsides</span>


    -Greater recoil impulse means longer recovery time for a second aimed shot
    <span style="color: #FF0000">A properly set-up 6.8SPC is very similar to the 5.56. There was an independent test conducted that proved it. DocGKR actually posted the times and the 6.8SPC was actually a fraction of a second faster in CQB drills. I know you are going to say I'm full of shit, but facts are facts.</span>

    </div></div> </div></div>

    I'm not going to say you are full of shit, but I am going to suggest that perhaps the reason you believe this has more to do with Bias than Fact. The 6.8 ejects greater mass in both bullet and gasses, which means it will have a greater gross recoil, if the weapon systems are the same, it should have greater NET recoil. That's basic science. If you make claims contrary to established science, you need to come up with some compelling reason why we should believe the world is flat.

    </div></div>


    Jim, I am not interested in getting into a fight with you over the 6.8. You are the one that clearly seems biased against the 6.8. Why, I don't know. Have you ever fired one? Do you know what the recoil impulse feels like? You seem to believe that the only viable purpose for it, is in the US military. If that were true, we could then argue its merits or disadvantages based solely upon military / tactical considerations.

    But, since Paulosantos refuted every disadvantage you brought forth, and you still are telling us the round is not as good a 5.56, I find it completely worthless to argue with you.

    I simply came here to post this for those that want to know more about the round. Many of these guys are hunters and LEO's. The will not care about magazine capacity or 1-2 ozs of weight in carrying ammo. If they did, they could simply buy Barrett mags and get 30 rounds. In my opinion, a 6.8 rifle will outperform the 5.56 in any scenario you can imagine. That comes from 5 years of experience shooting and reloading for both, and hunting with both, killing hundreds of animals.

    There really is no comparison whatsoever, for me, anymore. the 6.8 SPC has made my 6 lb AR-15, with its 12 inch barrel, a completely viable hunting weapon, whereas before, it was a crippler. If you can bring that same level of experience to this forum (after doing the same ting with 6.8 SPC) and you have a different opinion, then I suspect members will want to hear it. If you have no experience with the 6.8, then I would suggest you try it....you might be surprised at how little you really know about it.
     

    HTR707

    Sergeant
    Commercial Supporter
    Full Member
    Minuteman
    May 12, 2008
    228
    0
    Rockport, TX
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: paulosantos</div><div class="ubbcode-body">Chris, I told you that you were just wasting your time posting it here. I think you'd have better luck posting it on the Grendel Forum.
    laugh.gif
    laugh.gif
    laugh.gif
    </div></div>

    I'm not giving up. My ego doesn't get bruised easily. People are often skeptical about new things for good reasons. I can understand it.

    I simply came here to update everyone with information about how far this cartridge has come in the last few years. I think there are sure to be some guys that are wanting to try it. I hope that I could at least help them with their choice if they are considering a 6.8. It will certainly make the AR-15 a much better hunting rifle, especially if you are after medium-sized game.
     

    BALLISTIC

    Jack of all Trades
    Full Member
    Minuteman
    Dec 31, 2002
    241
    34
    Vinland
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    It still fires a .277 projectile, and that means it SUCKS. .277 caliber is the bastard caliber compared to nearly every other caliber for distance shooting.

    A .277 85 grain barnes with a bc of .246 at 3100fps still loses versus a .224 62 grain barnes with a bc of .287 going 3100fps.

    I think whoever created the round is mathematically retarded. The only thing the 6.8 has over 223/5.56 is energy. Well DUH! It fires a much heavier bullet. If they wanted a superior round than a 223/5.56 they could have used the same case, but instead neck it for a caliber worth a damn. .243 would be my choice, but .257 or .264 would be good too.

    The 6.8SPC or 6.8SPC II is still going backwards. If they were only looking for more energy then the 30 Rem would be better than the 6.8, but then they wouldn't have 'created' anything.

    And as far as the 'killing power' of 6.8. It's nothing special because 22lr and 30/30 have killed anything and everything, so that is pointless. Any rifle cartridge will get the job done, only some make it easier. And I would take a 30 Rem over a 6.8 any day.
     

    HTR707

    Sergeant
    Commercial Supporter
    Full Member
    Minuteman
    May 12, 2008
    228
    0
    Rockport, TX
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: BALLISTIC</div><div class="ubbcode-body">It still fires a .277 projectile, and that means it SUCKS. .277 caliber is the bastard caliber compared to nearly every other caliber for distance shooting.

    A .277 85 grain barnes with a bc of .246 at 3100fps still loses versus a .224 62 grain barnes with a bc of .287 going 3100fps.


    <span style="color: #FF0000">Yeah, sure.....50% more bullet weight...same bullet design.....same speed. BC is everything...ask all the animals I have killed with the 85 TSX....I am sure they knew the BC and that it sucked. Good God, man....
    confused.gif
    </span>

    I think whoever created the round is mathematically retarded. The only thing the 6.8 has over 223/5.56 is energy. Well DUH! It fires a much heavier bullet. If they wanted a superior round than a 223/5.56 they could have used the same case, but instead neck it for a caliber worth a damn. .243 would be my choice, but .257 or .264 would be good too.

    <span style="color: #CC0000">All these have been tried. The 5.56 X 45mm parent case is not efficient when compared to the .30 Rem case. You cannot get the same velocity without over-pressure. The 6MM Kramer is not gaining in popularity, for some reason, even though you back it.</span>

    The 6.8SPC or 6.8SPC II is still going backwards. If they were only looking for more energy then the 30 Rem would be better than the 6.8, but then they wouldn't have 'created' anything.

    <span style="color: #FF0000">You make so little sense here, I cannot possibly comment. Remington release the "30 Remington AR," this year. What a joke. Another cartridge that claimed 2800 FPS, only to deliver 2200. It is the 7.62 X 39....like we needed another one of those. The AR-15 now can shoot a 100 grain projectile, despite magazine length restrictions, at 3000+ FPS (the Grendel is also doing this, which I find pretty, coo, too). This is the first time. This is a simple fact. </span>

    And as far as the 'killing power' of 6.8. It's nothing special because 22lr and 30/30 have killed anything and everything, so that is pointless. Any rifle cartridge will get the job done, only some make it easier. And I would take a 30 Rem over a 6.8 any day. </div></div>
    <span style="color: #CC0000">
    My guess is, that you would obviously know because you have killed so many animals with it. I cannot get my .22LR to shoot 85 or 100 grain bullets at 3000 FPS, despite my Spike's tactical conversion kit, dang it. And I have not seen a 30/30 that will fit in an AR-15 mag, have you?</span>

    Some of you guys amaze me. But you are entitled to your opinion.


     

    BALLISTIC

    Jack of all Trades
    Full Member
    Minuteman
    Dec 31, 2002
    241
    34
    Vinland
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    LOL good job of talking circles to my points. You sound like a politician. Let me break it down for you, so there will not be any confusion on your end...

    What does the 6.8 do better than a 223/5.56 other then provide more energy?

    EDIT: Oh and when I meant use the same case with another caliber, I was refering to the 6.8 or 30 rem case. Which would be a VAST improvement for such a simple change.
     

    HTR707

    Sergeant
    Commercial Supporter
    Full Member
    Minuteman
    May 12, 2008
    228
    0
    Rockport, TX
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    First, no body here is claiming this is a "LONG DISTANCE" , 1000 yard, sniper cartridge.

    But just so you know how bad it really is:

    Here is a picture of my first ever attempt at 500 yard silhouettes. Notice the rifle. It is a PENCIL BARRELED 6.8 SPC with 1:11 twist, SPCII chamber and 4 groove rifling. I was shooting Speer 90 grain TNT's with 29 grains Of RE7, at 2950 FPS.

    Sights: UNMAGNIFIED Eotech 552 D1.

    This round is so poor, that I hit the 500 yard silhouette 5 of 8 shots at 500 yards, as you can see in the photo. Many of you believe the bullet falls harmlessly to the earth at 300 yards. It appears that it does not, after all.

    NOTE: I limit my shots at animals to no more than 250-300 yards, because that is the distance that I believe these medium cartridges will humanely kill them.....including when I use my .308....but, then again, it weighs 11 pounds and my 6.8 weighs 6.



    Longrangeshoot030.jpg
     

    BALLISTIC

    Jack of all Trades
    Full Member
    Minuteman
    Dec 31, 2002
    241
    34
    Vinland
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    More circle talk...I politely request that you answer my question.

    As far as the making it to 500yards...that is just comic. I mean shit a 45/70 can make it accurately past 1000 yards and its BC is even worst than a 6.8, but that is besides the point.

    I am not attacking 6.8's existence, but rather I am attacking the fact that MOST 6.8 shooters claim it is better than 223/5.56, but when I question them about it they cannot provide any logical reasoning. There are many cartridges that I think are retarded, but it doesn't bother me. What bothers me is when someone claims something is better, but cannot prove it.
     

    Cixelsyd

    LUSH
    Full Member
    Minuteman
    May 17, 2004
    130
    0
    W-NC
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    That 6.8 weighs six pounds with a can on it?
    shocked.gif



    Just flying in from active topics.

    CHRIS
     

    HTR707

    Sergeant
    Commercial Supporter
    Full Member
    Minuteman
    May 12, 2008
    228
    0
    Rockport, TX
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: BALLISTIC</div><div class="ubbcode-body">More circle talk...I politely request that you answer my question.

    As far as the making it to 500yards...that is just comic. I mean shit a 45/70 can make it accurately past 1000 yards and its BC is even worst than a 6.8, but that is besides the point.

    I am not attacking 6.8's existence, but rather I am attacking the fact that MOST 6.8 shooters claim it is better than 223/5.56, but when I question them about it they cannot provide any logical reasoning. There are many cartridges that I think are retarded, but it doesn't bother me. What bothers me is when someone claims something is better, but cannot prove it. </div></div>


    DON'T TAKE MY WORD FOR IT:

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


    <span style="color: #CC0000">"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?
    </span>

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

    <span style="color: #FF0000">".......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:
    &#61607; <span style="font-weight: bold">“The best performing systems emphasizing tissue damage, on the average, in this
    study were of larger caliber than 5.56 mm.</span>”
    &#61607; “The 6.8 mm performance observed in this test suggests that an intermediate
    caliber is the answer to the trade-off balance issue.”
    &#61607; <span style="font-weight: bold">“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.”</span>
    &#61607; <span style="font-weight: bold">“The 6.8mm SPC is far and above, the best performing ammunition…”</span></span>

    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, and to how weak the 5.56 was in killing hogs and deer by comparison....hundreds.

    There you have it. No circles.
     

    HTR707

    Sergeant
    Commercial Supporter
    Full Member
    Minuteman
    May 12, 2008
    228
    0
    Rockport, TX
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Cixelsyd</div><div class="ubbcode-body">That 6.8 weighs six pounds with a can on it?
    shocked.gif



    Just flying in from active topics.

    CHRIS </div></div>


    No, I am sorry....with the can on it, it weighs about 7. The can only weighs 15.7 ozs and is made of Titanium.
     

    HTR707

    Sergeant
    Commercial Supporter
    Full Member
    Minuteman
    May 12, 2008
    228
    0
    Rockport, TX
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    Before we even go any further....

    Let me just say this: I am not here to convince anyone to sell their other rifles and change over to 6.8 X 43 mm SPC.

    When you ask me to support to you why I think it is better than 5.56, I will try my best. But, if you were to come to my ranch, and you wanted to recover the meat from a wild hog, feel free to use 5.56, while I shoot 6.8 SPC, with Barnes 110 grain TTSX's. We will see who actually recovers more of the pigs they hit. With the vast experience I have there, my bet is that it will be me. You are free to believe whatever you like.

    For those of you that are interested in this caliber for your AR, ask away. If you hate the whole idea, I am not too sure why you would even want to post here....unless it is just to stir up shit.

    But thanks to those of you who have good constructive criticism or input, as that does help everyone.
     

    BALLISTIC

    Jack of all Trades
    Full Member
    Minuteman
    Dec 31, 2002
    241
    34
    Vinland
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    LOL!!! The biggest of all circles! I won't 'take your word for it' because I love to challenge things.

    In regards to the 223/5.56 not having adequate terminal performance that is partly a bullet issue, NOT A CARTRIDGE ONE. A FMJ doesn't provide as much terminal performance as a soft point. And the other part of 'terminal performance' issues are usually problems of marksmanship, and not the cartridge's fault. If I shoot you in the foot with a .505 Gibbs, you will still live, but if I shoot you in the heart with a 45 colt, you are going to die.

    The idea of the 223/5.56 not punching through barriers as well as a 6.8 is based on 2 things. Bullet construction and energy in relation to diameter. With a similarly made bullet the 6.8 would only be better when it's energy in relation to it's diameter was higher than a 223/5.56's. I am too lazy to actually try to create some formula to rationalize it for you, and most likely you wouldn't understand it anyways, but suffice to say I highly doubt it has much, if anything, over 223/5.56 within 300 yards, and definitely doesn't have it beyond that.

    <div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">“The best performing systems emphasizing tissue damage, on the average, in this
    study were of larger caliber than 5.56 mm.”</div></div>

    Well no shit...you mean a projectile with a larger diameter is going to cause more tissue damage? That is so simple a 5 year old knows it, and this <div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">Doctor</div></div> had to conduct a study to figure that out? Damn, what a waste of time, energy, and money. I have met a couple people who are 'doctors', not medically, but with PHDs, and I can attest to the fact of having a doctorate does not make one smart, it only proves that they are determined enough to stick it out long enough to get one. I have met some retarded 'doctors', and I have met some very intelligent people who never even completed high school.

    I find it funny that you get sooooo excited and upset when someone calls you out on your 'precious', but at the same time I find it rather sad. I only wish you to come to the realization that your 'precious' 6.8 isn't better, it just has more 'hype'.
     

    BALLISTIC

    Jack of all Trades
    Full Member
    Minuteman
    Dec 31, 2002
    241
    34
    Vinland
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    I highly doubt a pig would notice a difference between a .277 110 grain barnes and a .224 70 grain one.
     

    ubershinobi

    Private
    Minuteman
    Jan 15, 2007
    49
    0
    California
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    Glad to hear the 6.8 still has a strong following trying to improve the round. Like anything new, it takes lots of work and testing to get it perfected. This ability is what makes our future weapons even more deadlier with the wealth of information you guys come up with.

    Stay motivated.
     

    BALLISTIC

    Jack of all Trades
    Full Member
    Minuteman
    Dec 31, 2002
    241
    34
    Vinland
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    Except when the direction the work is going is backwards, then it is only pointless work. The only way to 'improve' the 6.8 is to scrap it and get something else. :p
     

    bustin

    Sergeant
    Full Member
    Minuteman
    May 6, 2008
    581
    0
    50
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: BALLISTIC</div><div class="ubbcode-body">It still fires a .277 projectile, and that means it SUCKS. .277 caliber is the bastard caliber compared to nearly every other caliber for distance shooting.

    A .277 85 grain barnes with a bc of .246 at 3100fps still loses versus a .224 62 grain barnes with a bc of .287 going 3100fps.

    I think whoever created the round is mathematically retarded. The only thing the 6.8 has over 223/5.56 is energy. Well DUH! It fires a much heavier bullet. If they wanted a superior round than a 223/5.56 they could have used the same case, but instead neck it for a caliber worth a damn. .243 would be my choice, but .257 or .264 would be good too.

    The 6.8SPC or 6.8SPC II is still going backwards. If they were only looking for more energy then the 30 Rem would be better than the 6.8, but then they wouldn't have 'created' anything.

    And as far as the 'killing power' of 6.8. It's nothing special because 22lr and 30/30 have killed anything and everything, so that is pointless. Any rifle cartridge will get the job done, only some make it easier. And I would take a 30 Rem over a 6.8 any day. </div></div>

    So how long is this 5.56 barrel that shoots a 62gr at 3100fps? I believe the M855 is loaded to 58000 psi and shows swipes on almost every case I have fired in the last 20+ years. I believe the mil spec M855 ammo hits 3100 from a 20" barrel and the M193 load hits 3200 from a 20" so how fast are they from a 16"? The 3100fps load HTR speaks of comes from a 16" 6.8 and can be loaded to 3200fps from a 16" barrel.


    The designers of the 6.8 tried every caliber, the .277 produced better terminal ballistics to 300 yards(which was the design parameter set by the team) but, I guess you knew that. The case capacity to bore area ratio makes the 6.8 more efficient than the 30BR which is considered one of the most efficient calibers, just ask any benchrest guy.
    To fit in a AR mag the bullet cannot be too long, thats why you can't use a .500 BC .243 bullet, or a high BC 6.5 bullet.
    You have to take everything into consideration when designing a round, you can't just neck something down and slap a long bullet in it if you want to shoot it from an AR.
    If you use 30 cal bullets in the 30Rem case they would be slow due to weight, and have a worse BC than those .277 bastard bullets you hate so much if you get them down to the same weight in order to obtain the same velocities.
    Any bullet of a smaller dia will decrease the bore area to case capacity ratio making it less efficient and slower, any larger dia bullet increase weight or lowers BC so the designers werent't mathematically retarded you just can't see how smart they were.
    Velocity can overcome alot of BC out to 300 yards which again is considered the limit of most M4s.
    Don't worry no one is knocking on the door of the 308 for the sniper caliber.
    adios cali

    ETA- Can you tell all of us what 16" combat rifle(the size if an AR, not a 16" 50 cal) and what load at 100yds will defeat every body armor currently built?
     

    BALLISTIC

    Jack of all Trades
    Full Member
    Minuteman
    Dec 31, 2002
    241
    34
    Vinland
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    I was comparing ballistics, but wasn't thinking about specific barrel lengths. I assume it would be a 20in. If a 55 can get to 3250, then I don't see why a 62 cannot get to 3100, and if you really want to get accurate then for a 16in barrel assume 3000fps, and it would still be better than the 6.8.

    I am curious as to how/why the .277 produced better terminal ballistics than .243, .257, .264, .284, and I would also like to know if they used the same bullet for each caliber.

    I never said to use the highest bc bullets either, but lightweight bullet as a 70-85gr .243, 90-100gr .257, 100-110gr .264, 120-130gr .284, or 130-140gr .308 would be better than the 115 6.8, and I would think they might be capable of fitting it the magazine.

    A 135gr SMK in .308 has a bc higher than the 115 6.8 and it's not a very long projectile, but I don't know if it would work in a AR mag adequately. It's velocity would not be as high as the 6.8, but I think it could be just as good if not better.

    ETA: I haven't tested ANY rifle against ANY body armor, let alone ALL body armor, so I don't know. What's the point of the question?
     

    bustin

    Sergeant
    Full Member
    Minuteman
    May 6, 2008
    581
    0
    50
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    Not sure about the terminal performance other than the 6.5 projectiles in the usable weight range are mostly match and varmint style bullets, the 7mm bullets in the usable weight range are mostly varmint type bullets. There have been several .277 bullets developed specifically for the 6.8 in the last 3 years which improved the performance even further.
    There are 95gr frags, 97gr APs at 3000fps to answer your question about the armor, 85 TSXs that the FBI wanted to try, the 100 Nosler accubond also an FBI initated projectile, A 99gr turned and banded solid copper. The 115 SMK works but the 135SMK is slightly heavy for a case that size. Hornady has a 110gr OTM.
    All I am saying is there has been enough interest in this caliber to develop several projectiles for specific uses, a few more are on the way according to my contacts.
     

    HTR707

    Sergeant
    Commercial Supporter
    Full Member
    Minuteman
    May 12, 2008
    228
    0
    Rockport, TX
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: BALLISTIC</div><div class="ubbcode-body">I highly doubt a pig would notice a difference between a .277 110 grain barnes and a .224 70 grain one. </div></div>

    The things you highly doubt are, no doubt, things in which you have NO experience.

    The 70 grain .224 TSX will require at least 20" of barrel to achieve the same velocity as the 110 grain TTSX fired from a 6.8 SPC, which has a larger cavity and happens to open up at a lower impact velocity than the TSX. I get mine going to 2700 FPS in a 16" barrel. Sorry, but currently, there is no tipped TSX in .224. So, when you talk about not having good bullets for the 6.8, I can point to one that is NOT EVEN AVAILABLE FOR the 5.56.

    You appear to have no direct experience, with the 6.8. I have to wonder if you have ever even laid hands on one.

    We state facts to you, and you still talk conjecture and bullshit. You are obviously just here to throw rocks.

    When you have gained some field experience with hog killing, please come back and argue with me some more. Go right ahead and believe whatever you like. Please feel free to buy 5.56 ammo when you go pig hunting.

    If you really hunted, you wouldn't even be saying this stuff, so there is just no point. You haven't even seen the difference in these two cartridges in the field. I have and I have seen a major difference in the way the 6.8 incapacitates huge hogs versus the 5.56. Sure, if you hit them in the brainstem you can kill them with the .17 Remington or HMR. But we often have to shoot them on the run.

    The 85 TSX and the 110 TTSX are the ONLY TWO bullets I have ever seen go completely longitudinally through a pig, from chest to hip and out the other side.

    I have shot them with 22 LR, 22Mag, .223 & 5.56 of every bullet weight and type imaginable, 6mm Rem, .308, .44 magnum, 7MM, .45-70 and 6.8 SPC. It is not a magic death ray, but it is the first cartridge that allowed me to use a 16", 7 lb AR, and knock down huge pigs with a single shot, with a very high percentage.

     

    silver78

    Sergeant
    Full Member
    Minuteman
    Nov 2, 2004
    121
    0
    61
    MD
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: HTR707</div><div class="ubbcode-body">

    It is very important to note that even if you bought any of these barrels from any manufacturer, converting the SAAMI to SPC II chamber is ridiculously easy, by reaming out to the extra freebore, then equaling .100" which is .050" greater than the SAAMI.

    </div></div>

    So does this mean that any of the old barrels that are reamed as you describe will be safe to use with todays hot loads? If I recall correctly there was also a change in thinking on twist rates and I wonder if an older barrel with a fast twist rate will still exhibit problems even if reamed. Sorry - I'm no expert on this. I just want to make sure that everyone who wants to shoot the 6.8 is doing it in a safe manner.
     

    Bart

    Private
    Supporter
    Full Member
    Minuteman
    Feb 13, 2005
    235
    57
    Amarillo, Tx
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    HTR and paulosantos-

    Thanks, and keep up the good work!

    I have been using the 110 Hornady, I will try the TSX next.

    Currently using reloder 10X, is there a better powder?

    I dont know if the 6.8 is making my mouse gun "roar", but it damn sure makes it speak with more authority!

    Thanks again,

    Jordan
     

    fireball168

    Sergeant
    Full Member
    Minuteman
    Sep 27, 2006
    143
    0
    Clinton, IN
    www.bfgcartridges.com
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: HTR707</div><div class="ubbcode-body">

    Remington release the "30 Remington AR," this year. What a joke. Another cartridge that claimed 2800 FPS, only to deliver 2200. It is the 7.62 X 39....like we needed another one of those.

    Some of you guys amaze me. But you are entitled to your opinion.
    </div></div>

    Shooting Times Review:

    http://www.shootingtimes.com/longgun_reviews/ST_r15andthe30rar_200905/index2.html
    <span style="font-style: italic">
    I shipped off some pre-production factory ammo--123-grain Metal Case (MC) and 125-grain Core-Lokt PSP--then I boarded a plane for San Antonio. Average muzzle velocities for <span style="font-weight: bold">10-round strings from the 22-inch barrel were 2,721 fps for the MC and 2,770 fps for the Core-Lokt</span>, slightly down from the advertised 24-inch-barrel numbers of 2,800 fps. </span>


    It would appear that Remington has done something with the additional 8 grains of H20 capacity this cartridge has over the 7.62x39.
     

    Mac679

    Private
    Full Member
    Minuteman
    Nov 8, 2008
    60
    30
    CONUS
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: BALLISTIC</div><div class="ubbcode-body">It still fires a .277 projectile, and that means it SUCKS. .277 caliber is the bastard caliber compared to nearly every other caliber for distance shooting.

    I think whoever created the round is mathematically retarded. The only thing the 6.8 has over 223/5.56 is energy. Well DUH! It fires a much heavier bullet. If they wanted a superior round than a 223/5.56 they could have used the same case, but instead neck it for a caliber worth a damn. .243 would be my choice, but .257 or .264 would be good too.

    The 6.8SPC or 6.8SPC II is still going backwards. If they were only looking for more energy then the 30 Rem would be better than the 6.8, but then they wouldn't have 'created' anything.

    And as far as the 'killing power' of 6.8. It's nothing special because 22lr and 30/30 have killed anything and everything, so that is pointless. Any rifle cartridge will get the job done, only some make it easier. And I would take a 30 Rem over a 6.8 any day. </div></div>

    Got your panties in a wad because someone didn't do what you'd do? I'm pretty sure the guys from 5th Special Forces Group who initiated the cartridge know far more about killing people than you do. You might want to leave that topic to them. I'm also pretty sure that the Army Marksmanship Unit who were involved in the development also have forgotten more about shooting and ballistics than you've learned.
    6.8 was never intended as a long range cartridge. It's not some super duper sniper round to bridge the gap between 5.56 and 7.62. It was designed to put people down quickly and effectively at typical engagement distances (0-200m). Again, I'm pretty sure a bunch of Special Forces senior NCOs know more about this task and what is needed to accomplish it than you do. The other concern to the program was that it must be capable of being fired out of the existing M4 recievers already in the arsenal. They actually developed a superior cartridge to 6.8, but it was a 7mm based cartridge (the exact chambering escapes me at the moment), but it could not be fired from the existing platform.
    You like to quote the numbers, why not check the ballistic gelatin tests and check the permanent wound channel and fragmentation vs 5.56.
    And I'm pretty sure that for combat purposes, the lightweight bullets weren't the intended rounds. Might have been something along the lines of a 115gr SMK (OTM as the military calls them) round.
    .22LR and 30/30 eh? Ever cleared rooms down range? Tell you what, try it with a .22LR and let me know what you think of it.
     

    paulo_santos

    Sergeant
    Full Member
    Minuteman
    Jan 4, 2006
    491
    0
    47
    NJ
    www.spdcrossfit.com
    Re: Today's State of the Art in 6.8 X 43 mm SPC

    <div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Bart</div><div class="ubbcode-body">HTR and paulosantos-

    Thanks, and keep up the good work!

    I have been using the 110 Hornady, I will try the TSX next.

    Currently using reloder 10X, is there a better powder?

    I dont know if the 6.8 is making my mouse gun "roar", but it damn sure makes it speak with more authority!

    Thanks again,

    Jordan </div></div>

    RE10X and H335 are the two best powders for those bullets. H322 is also good, but you ca only stuff 29.5 GR in the case because it gets too compressed past that. If you have a good barrel, you should be able to stuff 29.5 GR of 10X, which will produce great velocities and accuracy. I never had much luck with the Hornady 110 GR BTHP bullets in any of my barrels. I had decent luck with the V-Max bullets with H322. The problem with the Hornady bullets is thier retarded Secant Ogive, which is good for terminal ballistics, but pain in the butt for accuracy.