Clearly, the only reasonable answer is… LASERS!

That being said I’m building a 6.8 as a hunting rifle.  If you read the 6.8 FAQ, you’ll see that the round has been quite effective against zombie deer.

Quoted: Will try and get this done tomorrow and post results; the 6.8 SPC is truly an outstanding cartridge.

Hey, the 6.8 is a great round. Get it adopted.






[ man, I'm on a roll ]

rj

Quoted: the 6.8 SPC is truly an outstanding cartridge.

Compared to what, and in which way?

The 6.8 or any other cartridge for that matter will not be fully adopted by the Military at least in my life time. Lake City is the only Small Arms Plant in the States, to change it would be a major undertaking.  Then all the weapons would have to changed, not to mention getting all the NATO countires to agree (ya- right, the French & Germans).

The Special Ops boy's that get into and out of engagement's will switch slowly. They need something with more punch close in, not something that shoots 600 yards down range. They will not need the massive numbers of ammo as compared to the 5.56.

You will never see the ammo price of the 6.8 or the Grendel down to the level of the 5.56. Thats because of the massive production capablities now in place for the 5.56, not only in the States but world wide. The 5.56 production facilities are so highly automated today its scary, how about several 1,000 rounds per minute thru Lake City alone.

The 6.8 is further down the road then the Grendel with several gun companies already making some very nice weapons in 6.8 here in the States and another one coming on line from overseas.

You can get  2,600 FPS out of a 16 inch barrel with the 6.8 from a 110 or 115 grain projectile. If you drop the weight ,yes you can get it to go faster but why? Its a closer in type weepon where I would want more weight in my projectile not speed. Of course I am looking at it from a Military view point.  

Just my own prospective on things for whats it worth.

Art - Silver State Armory

It's interesting to note that SOCOM specified a 7.62x51 version of the SCAR rifle as well as 5.56mm (and of course 7.62x39, but that was for other reasons). I presume that the people currently pondering the lessons of Iraq and their implications for the proposed new family of small arms will be thinking about this.

I don't pretend to be a mind-reader but I would guess that one of the debates will be between bringing back 7.62x51 rifles in much bigger numbers to use alongside 5.56mm rifles (and putting up with the weight and recoil plus the issuing and supply problems), or getting something bigger and more effective which will fit into 5.56x45 weapons.

If they're thinking about something bigger than 5.56mm, then they have a straight (but not very easy) choice: the 6.8mm, which is probably the optimum choice for use in rifles up to 300m, or the 6.5mm, which offers a long-range performance good enough to replace the 7.62mm weapons at some point, providing some real benefits (MUCH lighter MGs and ammo than the 7.62mm)

After all, the proposed US replacement of ALL 5.56mm weapons presents a once-in-every-couple-of-generations chance to consider a calibre change - and I don't think they'll waste much time thinking about NATO.

Tony Williams: Military gun and ammunition website and discussion forum

I've heard it said alot of times that the 6.5 can shoot with the 7.62x51, but I have a hard time believing it, I am certainly not an expert, but aren't there 7.62 caliber bullets out there with equally good BC's, and some that are even better? I don't know if these high BC bullets are significantly heavier, and thus sacrifice muzzle velocity, but if they don't then you have a heavier bullet with equal or better BC at comparable muzzle velocity. Even with my limited knowledge of ballistics, I know that equates to superior downrange energy. If anyone can elaborate on the "6.5 beats .308" argument i'd appreciate it.

Art wrote: "You can get 2,600 FPS out of a 16 inch barrel with the 6.8 from a 110 or 115 grain projectile."

Art, a very interesting statement, and of the kind I admit I've been harping about. Hodgdon gets 2608 fps with a 115 gr in a 24" bbl at a pressure of 53,300 psi.

The crucial question is: What is your pressure for your "2600 from a 16"?

John

Quoted: I've heard it said alot of times that the 6.5 can shoot with the 7.62x51, but I have a hard time believing it, I am certainly not an expert, but aren't there 7.62 caliber bullets out there with equally good BC's, and some that are even better? I don't know if these high BC bullets are significantly heavier, and thus sacrifice muzzle velocity, but if they don't then you have a heavier bullet with equal or better BC at comparable muzzle velocity. Even with my limited knowledge of ballistics, I know that equates to superior downrange energy. If anyone can elaborate on the "6.5 beats .308" argument i'd appreciate it.

Basically you're right: a good big one will always beat a good little one. But....

The 6.5mm with the Lapua Scenar 123 grain bullet will better the trajectory of the standard 7.62mm M80 (150 grain) ball round and retains more energy from 600m onwards. The long-range 7.62mm M118LR 175 grain loading retains more energy than the Scenar, but the trajectory isn't as good. However, you can get a 144 grain Lapua 6.5mm loading which pretty well matches the M118's retained energy at long range, and still has a better trajectory. You can no doubt get a very-long-range 7.62mm loading which will retain more energy than the best 6.5mm, but the trajectory will be even worse.

The 7.62mm will always make a bigger hole in the target, but you pay for it in recoil (about double) and higher ammo and gun weight.

Tony Williams: Military gun and ammunition website and discussion forum

Ok, I can believe that, can anyone give some hard numbers on all of the above, like muzzle velocity, retained energy, trajectory degradation, etc. out to say 1,000 meters. I know thats's a tall order but it doesn't hurt to ask. Also what does a loaded 7.62x51 weigh compared to a loaded Grendel, never even held a Grendel before so kinda curious about this.

The only thing I question is the terminal performance of the lapua scenar's, if they don't have good terminal perfomance, then doesn't that make the rest of their statistics moot? ( As a combat round I mean) So how good are their terminal effects?

Panzer, 6.5 Grendel and 7.62 NATO ballistics are here: www.65grendel.com/graphics/grendelballistics.pdf.

If you want to play around with your own numbers, try here: www.eskimo.com/~jbm/ballistics/traj_basic/traj_basic.html.

John

P.S. I suggest further 6.5 Grendel discussion be moved to a Grendel-specific thread.

Quoted: Art wrote: "You can get 2,600 FPS out of a 16 inch barrel with the 6.8 from a 110 or 115 grain projectile." Art, a very interesting statement, and of the kind I admit I've been harping about. Hodgdon gets 2608 fps with a 115 gr in a 24" bbl at a pressure of 53,300 psi. The crucial question is: What is your pressure for your "2600 from a 16"? John

John,

We use a powder that is blended for us just for the 6.8 we do not buy off the shelf powders. By buying this way we can get max perfornance for our given requirements. Our pressure from a 16" barrel (at 2,600 FPS) is 52,500 PSI. Our loads with Match Kings and Pro Hunters are getting 1/2 MOA at 100 yards, as reported by PRI, Ratworks and several other gun manufactures. An up coming article in a trade publication will varify these findings. The article is about the Barrett Rifle using several brands of ammo, I'll just say we really like this article.

Keep in mind more pressure does not always mean more velocity, in addition more powder does not always mean more velocity,  some of you now think I'am nuts. It's the burn rate of the powder thats most important, if the pressure peaks too fast the barrel becomes resistence to the bullet (higher pressure lower velocity). If the burn rate is too slow you will have lower velocities, a nice flame thrower and you will loose accuracy.

Pressure as you well know is a safety number not a proformance number and should not be related to velocity.

As an ammition manufacture we have to find a balance, we targeted the 16 inch barrel. If you really want to get the best preformance you would need a powder for each barrel length, twist, depth of lands, projectile weight, type of projectile and verious other factures that all affect pressure and preformance.

Art - Silver State Armory



 

Quoted: Our pressure from a 16" barrel (at 2,600 FPS) is 52,500 PSI.

One of the downsides to the "open" nature of the evolution of the 6.8SPC is that there is a wide varity of chamber dimensions out there being sold as "6.8SPC".     Has all of that settled down, or do various barrel makers still have different chambers?   If there are still diverse chambers being produced, I'm curious which chamber you're testing against?

Quoted: i'v been away awhile what's the general concenses on the spc?

I don't post very often, but, I think that, after reading the FAQs currently available and then looking at this thread, you're about as educated as the rest of us!  Take what you know to be intuitively correct, trust your gut when it comes to any claims either way, and you're there.  This gets re hashed so often its actually becoming so nauseating that I long for the old days of the Oly bashers and Colt Kool Aid drinker threads.

Truth seems to be that, for once, someone listened to what the real trigger pullers wanted in terms of a round (to include caliber, bullet design, and accuracy potential) that fit the current M16 platform but had more wounding potential within 300m (which EXPERIENCE in the current war has shown is a valid engagement range) while capitalizing on the inherent accuracy potential of the precision M16 parts production capability without sacraficing long distance shot potential WHEN COMPARED TO THE CURRENTLY AVAILABLE 5.56 AMMUNITION LOADINGS WHEN FIRED FROM BARRELS OF 14.5 INCHES OR LESS as would be prefered in the current engagement when involved in heavy urban environments where short barrels become necessary/desirable.  There are a lot of parts of that statement that mostly seem to be ignored in the all too common caliber debate.  That being said:

[soap box mode on]

Here's how I sum up the current state of the 6.something debate, and there's NO WONDER that there's a ????? thread every two minutes, it's so frustrating to those of us who actually CARE and who have been around a while, imagine how a newbie feels?

Not matter what, as soon as you label a post "6.something" it turns into a Ford/Chevy/Dodge/Import (6.5G/6.8SPC/.223 heavy match) debate, and usually degenerates rapidly.  

6.5 lovers want to point to the 6.8 and say:
"....but it simply can't compete with the 6.5 out to (fill in the range here) with (fill in the number here" ft/lbs of energy"
"....6.5 a precision platform optimized for (fill in the range here), and the 6.8 is limited to 300m"
"....NO FAIR, the first tests in gel were not with bullets designed to tumble in flesh!"
"....WE'RE the only ones that have ammo available!"
"....you got squat for bullet selection!"
"....you'll never have to worry about CQB and 12 inch barrels if you use the G!  It's like a [dr.evil]fricken laser[end dr.evil] man"
"....HAHAHAHAHAH, we got ammo!"

6.8 lovers point to the 6.5 and say:
"....but you have to go through some goofy ritual sacraficing chickens at the Equinox to get the non standard parts that are used"
"....but your bullets don't tumble.  I want BIG wounds, not [dr.evil]fricken laser[end dr.evil] holes in Jihad Joe"
"....cut your barrel to 12 inches like mine is, Grendel Boy, and lets see your precious ballistics and down range energy numbers then!"
"....yeah, we screwed the pooch on initial ammunition availability, but you STILL can commercially only get yours from 1 place and our will be EVERYWHERE in just a few weeks!"
"....how much am I gonna have to pay for an upper?  I can't get a reamer to do my own?  You're gonna SUE ME for even trying?  F U!  We got reamers for almost FREE!"
"....I see you are using a magazine to feed your ammo that is sold as an SPC magazine.  Good choice!"

5.56 Heavy Match shooters point at both of 'em and say:
"...um, my Mk262 mod (fill in the number here) works just fine from (fill in the range here) to (fill in the range here)"
"....um, I ain't got NONE of your problems!  HAHAHAHAHAHAHAHAHAHAHAHAHAHAH!"

And on and on and on and on.

In short, most of the internet commandos are comparing apples to oranges.  I did like a few others did, I bought one of each.  I enjoy both.  They both have their merits to me, and I would choose one or the other based on my intended application, which is something that a non combatant has the luxuary of doing, where as GI Joe does not.  I also participated in the much vaunted Big Bore debate with my check book-458 SOCOM, .499LW, and 50 Beowulf.  I kept the 458 for a variety of reasons.  Am I a fool?  Only time will tell.  I think that perhaps the market is large enough to accomodate a variety of price, quality, and availability levels.  204 Ruger DID NOT replace the 223 Rem or the 22-250 in the P dog towns, and, for a variety of reasons, I don't think that a 5.56 main battle weapon is going anywhere anytime soon.  Not that, it seems, 6.8 was ever intended to anyway, just that it's suitability for replacing the 5.56 has been looked into.

There are a few, and precious few, who go out of their way to compare like information and admit when they have factual gaps and are up front as to WHY they don't know.  Many of them are right here on ARFCOM, have compared the G and the SPC from day 1, and some of 'em even pull triggers in some capacity for a living.  I respect and commend their civil public discourse, especially those WITHOUT a product or investment other than their personal $ and time.  Not to invalidate those up front posters with a product, as many of them are on the level, too, and do not try to sell when the discussion is in the information forums.

[end soap box mode]

But here's to answer your question:
Like anything new, the SYSTEM is evolving.  6.8 SPC, when originally introduced had no brass, no bullets, and LOTS of uppers available from mild to wild, cheap to uber $$$.  The supply/distribution chain has changed such that you can even find cheap 1x brass on Ebay for less than .25 a case.  More bullets SPECIFICALLY designed for the 6.8 are available (I count 4 designated SPC, with at least 4 others that are suitable as well).  The potential of the cartridge is being developed and, at least from a consumer point of view, is gathering following and support at all levels of the industry.

Indeed, some of the best tube reamers are right here on ARFCOM and have turned out some excellent quality and priced items.

I will keep my 6.8 SPC DPMS unit.  I will purchase another and/or replace it soon with one that has a higher accuracy potential due to inherently better raw materials and closer tolerance machine work.

I guess only you can decide if any of the "alternate calibers" are going to fit your applications.  Just be careful that you don't get sold a solution and go in search of a problem.

Tom  


ETA rant.  Sorry, I had to get it off of my chest. BAD troll mall ninja!!    I think that I'll go buy another $1200 6.5lb carbine and hang $1000 and 6lbs of shit on it now!

Quoted: Quoted: Our pressure from a 16" barrel (at 2,600 FPS) is 52,500 PSI. One of the downsides to the "open" nature of the evolution of the 6.8SPC is that there is a wide varity of chamber dimensions out there being sold as "6.8SPC".     Has all of that settled down, or do various barrel makers still have different chambers?   If there are still diverse chambers being produced, I'm curious which chamber you're testing against?

Griz

You are correct too many chamber related issues, I think it will still take  a little time to shake out.

Art - Silver State

Art and Randall,

Thank you very much for your FACTUAL information...a breath a fresh air amid the conjecture and innuendo often spouted around here.

Banzai, your second paragraph above was right-on!

Randall, I've conjectured that 6.8 SPC loadings might be at higher pressures than optimum, but your statement, "Dave also told me that the major makers have recently (last few weeks) been ordering new reamers with a longer throat to cure the high pressure signs with some of the current ammo," is the first time I've heard it admitted publicly.

What more can you say about this?

John

Quoted: Art and Randall, Thank you very much for your FACTUAL information...a breath a fresh air amid the conjecture and innuendo often spouted around here. Banzai, your second paragraph above was right-on!

+1 All the mine's bigger than yours gets a bit tiresome.

Quoted: Art and Randall, Thank you very much for your FACTUAL information...a breath a fresh air amid the conjecture and innuendo often spouted around here. Banzai, your second paragraph above was right-on!

DocGKR,

Yes, Banzai's 2nd paragraph again has hit the nail on the head again for about the nth time.
Since this thread has turned into yet another ARFDOM 6.8SPC v/s 6.5G pissing contest, have you gotten a 6.5G 14.5"-16" barreled upper from AA yet? If so, an ETA on testing results?

Thanks,
Pete

Edit for spelling...

Quoted: Shaw has opened up the bore dimension to account for chrome buildup, but NOT the groove dimension. What you end up with is a chromed bore of 0.2700" bore and 0.2762" when the dimensions should be 0.2700" and 0.2770"

I have a Shaw chrome barrel, and I was never able to make the same velocity as some of the other guys without seeing presure signs.  How dangerous is this situation?  If I use Hodgdon's max publised loads could this put me in danger?  

Thanks for your help.

Kris

I guess I knew you could not say.   But it is potentially a big deal?  I was thinking about a new barrel anyway

Quoted: I have a Shaw chrome barrel, and I was never able to make the same velocity as some of the other guys without seeing presure signs.  How dangerous is this situation?  If I use Hodgdon's max publised loads could this put me in danger?   Thanks for your help. Kris

What are you using the rifle for ?  If you are just punching paper you could load up the lightest .277 bullets and get higher velocity and lower pressures that way.  If you are deer hunting then you need the heavier bullets.  Mine is showing pressure with some ammo but not with the current Remington factory stuff.  I am going to keep my reloads pretty mild. For my uses 100 fps or so is not going to make any difference.  I did just order a box of the Barnes Triple X for possible use on hogs but I ain't gonna shoot nothing over about 75 to 100 lbs max.  

rj

Wonder if Stoney Point is making the modified 6.8 SPC brass for the COAL dohickey thingadobob?  I would really like to know the max COAL  I can safely use and make guestimation on the throat length.

I used a Brownell .270 Chamber Gauge (small piece of lead) and my chamber measured 1.800 exact.  Barrel is a WOA 18" std gas system.  

Quoted: Quoted: Barrel is a WOA 18" std gas system.   By std gas system, do you mean a rifle-length gas system? If so, I would be interested to know the gas port diameter.

Randall, sent you an IM and yes by std. I meant Rifle Length.

Quoted: Wonder if Stoney Point is making the modified 6.8 SPC brass for the COAL dohickey thingadobob?  I would really like to know the max COAL  I can safely use and make guestimation on the throat length. I used a Brownell .270 Chamber Gauge (small piece of lead) and my chamber measured 1.800 exact.  Barrel is a WOA 18" std gas system.

I don't see any on the Stoney Point website currently. I sent them a piece of brass and they modified it for me. Instructions are on the website. Price is $6.67 to do this. Turnaround was very quick too.

Quoted: Quoted: Wonder if Stoney Point is making the modified 6.8 SPC brass for the COAL dohickey thingadobob?  I would really like to know the max COAL  I can safely use and make guestimation on the throat length. I used a Brownell .270 Chamber Gauge (small piece of lead) and my chamber measured 1.800 exact.  Barrel is a WOA 18" std gas system.   I don't see any on the Stoney Point website currently. I sent them a piece of brass and they modified it for me. Instructions are on the website. Price is $6.67 to do this. Turnaround was very quick too.

Stoney Point told me that the most accurate use of their gauge is from a one-time fired piece of brass from the chamber that you wish to keep tabs on.  If you have another rifle of the same caliber then you should send in brass from that rifle.  Scribe info on the brass to keep them organized.

Dave S

Quoted: The cartridge was SAAMI approved around February of 2004, so there is no reason for the chamber dimensions to vary so widely. Of course any manufacturer can go have a reamer and gauges ground to different dimensions if they so choose, but you can be sure that the ammo makers are going to work to the SAAMI specs. I just talked with Dave Kiff at PTG about this. The following print is a SAAMI spec drawing: 6.8 Reamer Print Dave also told me that the major makers have recently (last few weeks) been ordering new reamers with a longer throat to cure the high pressure signs with some of the current ammo. He also said that the big "B" company went to a 0.100" long throat a long time ago. We also talked about the chrome lined shaw barrels that are avaialable. Shaw has opened up the bore dimension to account for chrome buildup, but NOT the groove dimension. What you end up with is a chromed bore of 0.2700" bore and 0.2762" when the dimensions should be 0.2700" and 0.2770" Dave asked me to post the following: "If you are having pressure problems with your current barrel, especially a chrome lined barrel, you can solve the problems by extending the throat to 0.100" long. PTG has carbide uni-throaters available that will cut through your chrome lining if required"

RR,  thank you for getting me back to this thread.

1) The upper part in red seems UNSAT.  Is there no recourse to spending half a grand on a complete upper and having a barrel that can't handle SAAMI spec ammo?  Yes, I already understand that most barrel manufacturers are not lawyers... but as a corporation they sure as hell have some on retainer.  Is there a consumer advocacy regulation that would cover this.

2) If having spent $500 on an upper with an UNSAT barrel and if the only recourse is:
    A)  to rebarrel
    B)  go FIND and then PAY someone to use a PTG gotta-chew-up your UNSAT chrome-lined barrel's throat reamer...................

just fuckinggoddamnsonofabitch forget it.

I BET THAT IS WHY BRAVO COMPANY SAYS THAT THEIR 6.8MM SPC UPPERS ARE BACK-ORDERED TILL mid-'06.  THEY ARE WAITING ON SHAW'S NEW AND IMPROVED WHILE BEING STILL FUCKED UP WITH UNSAT BORE AND GROOVE DIMENSIONED BARRELS.  

just da-da-damn

Dave{the fucking pissed-off and on Bravo Company E.R. can't get it fucking right Shaw barrelled upper owner} S

With only 25gr of H322 the primers are .

For the record!!!!!!!!!!!!!
In no way am I upset with Bravo Company USA/Paul.  
He has been and is First Rate.
I was only........VENTING.  Yeah, that's the ticket.  

Quoted: Wonder if Stoney Point is making the modified 6.8 SPC brass for the COAL dohickey thingadobob?  I would really like to know the max COAL  I can safely use and make guestimation on the throat length. I used a Brownell .270 Chamber Gauge (small piece of lead) and my chamber measured 1.800 exact.  Barrel is a WOA 18" std gas system.

You don't need a Stoney Point gauge.

Get this, this, a bullet comparator, a pair of calipers, a bullet, and a sized case and you can get not only comparator OAL when seated to the lands, but also set any jump you want.

Paul,
Thank you for your trademark lightning response.  

Dave S

BTW, you did see this at the bottom of my post, right?  

For the record!!!!!!!!!!!!!
In no way am I upset with Bravo Company USA/Paul.
He has been and is First Rate.
I was only........VENTING. Yeah, that's the ticket.


Thanks again.

Well if it's been a tough day, take heart, because the 20" 6.8 upper you sold me last spring has never had anything through it but handloads and I couldn't be happier with it, thanks.

ODG

Quoted: You don't need a Stoney Point gauge. Get this, this, a bullet comparator, a pair of calipers, a bullet, and a sized case and you can get not only comparator OAL when seated to the lands, but also set any jump you want.

When spend $40, when I only need to spend $10?  I all ready own the Stoney Point system, just need the case modified.

All the talk of undersized chambers/bores or whatever the issues are causing the problems with the 6.8 SPC has me a little bit intrigued.  The 5.56 Nato round is based off of the .222 Remington which is a SAAMI spec cartridge.  The Military did some tweaks here and there and came up with the 5.56 Nato.  So spec wise, the 5.56 chamber is a tad larger than the .223 Remington and the throat is a bit longer, primarily for added reliability.

Duh, old news.  Following this train of thought, why are there issues with the 6.8 SPC?  If development was co-sponsored by the Military, shouldn't the chamber and throat have the specs that would increase reliability in accordance with "loose as a goose".

If barrel maker XYZ knows to ream the chambers a tad larger for 5.56 Nato barrels they intend to chrome-line, then who had the brainfart not to ream the chambers a bit alrger on 6.8 SPC barrels they intend to chrom-line?

Or is this an issue with the the reamers out in the market place not being spec?

Who makes the barrels for DPMS?

(Theirs are NOT chrome-lined)

Quoted: Quoted: If barrel maker XYZ knows to ream the chambers a tad larger for 5.56 Nato barrels they intend to chrome-line, then who had the brainfart not to ream the chambers a bit alrger on 6.8 SPC barrels they intend to chrom-line? Or is this an issue with the the reamers out in the market place not being spec? That brain fart would be ER Shaw and/or Model 1 sales depending on who approved the reamer design to be purchased before work was started. The reamers available are made to the SAAMI specs as originally submitted by Remington. The reamers available "off the shelf" are not meant to be followed by a chrome lining job. You would specifically order a reamer oversize in critical areas such as the throat to make up for this.

Hell, Randall, it looks like E.R.Shaw doesn't even have a proper button for .270 Winchester... never mind a chrome'd 6.8!

Thanks for you input.  I always enjoy reading and learning from your posts.

Dave S

According to ER Shaw they do not offer bbls chambered in 6.8SPC.  Model 1 must be having their blanks chambered by someone else.  I have always heard that it was Bravo Company. Is this incorrect ?