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I can put same load in a 16" fast twist and 16" conventional twist in same price range and the conventional twist will shoot more accurate.I made no comments on pressure just fact that spin a bullet too fast it will act odd. Why I have 24" 5.56 barrels in 1:12, !;8 and 1:7.7. Based on bullet launched twist and accuracy can be directly affected.
 

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I'm thinking more along the lines of a 5R or 3R with a .090 freebore and a pressure reducing land/groove ratio.
When I took the time to look at SAAMI specs and ran the numbers for various .277 cartridges, I was surprised that most of the barrels that I have seen are undersized. Virtually all the .277's call for a 25/75 land-to-groove ratio. The only significantly different one was the new 6.8 Western, and it called for a 33/67 ratio which is still considered a "thin land" design.
 

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This thread is rapidly spinning off topic.

With all due respect to Litz, he just simply states bullets that are over spun do not fly nose high. His explanation says the same laws of physics do not apply to bullets as to artillery shells. Huh? When asked a string of serious questions to back up his statement, he uses a somewhat rambling analogy of a spinning top. The spinning top analogy actually points to the opposite of his claims. I do understand it is fashionable in this political climate to make a statement as fact with no real proof to back it up. I’m not saying his statement isn’t true, he just offers no real proof to back it up.

6.8 projectiles do have enough “power” to self destruct when over spun by 100,000 rpm. Ask Any machinist what level of damage can happen when objects are over spun buy just a couple thousand RPM. I have had 444 Marlin bullets self destruct when going from 1:36 to 1:12 twist. While the Marlin bullet is much bigger than a 6.8, it is certainly not an artillery shell. The energy in a spinning bullet can be greater than the energy of forward flight. This is especially true down range where the spin does not degrade like the forward velocity of the bullet.

Maybe a separate thread should be spun off to discuss bullet spin and gyroscopic affects?
 
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This thread is rapidly spinning off topic.

With all due respect to Litz, he just simply states bullets that are over spun do not fly nose high. His explanation says the same laws of physics do not apply to bullets as to artillery shells. Huh? When asked a string of serious questions to back up his statement, he uses a somewhat rambling analogy of a spinning top. The spinning top analogy actually points to the opposite of his claims. I do understand it is fashionable in this political climate to make a statement as fact with no real proof to back it up. I’m not saying his statement isn’t true, he just offers no real proof to back it up.

6.8 projectiles do have enough “power” to self destruct when over spun by 100,000 rpm. Ask Any machinist what level of damage can happen when objects are over spun buy just a couple thousand RPM. I have had 444 Marlin bullets self destruct when going from 1:36 to 1:12 twist. While the Marlin bullet is much bigger than a 6.8, it is certainly not an artillery shell. The energy in a spinning bullet can be greater than the energy of forward flight. This is especially true down range where the spin does not degrade like the forward velocity of the bullet.

Maybe a separate thread should be spun off to discuss bullet spin and gyroscopic affects?
The whole 'twist" of this story in its intent was just to say the 6.8 does not get hampered by a change of 1:10 to 1:9
Hardly enough to initiate projectile destruction in the 6.8 or an accuracy reducing effect.
However enough to add more terminal damage to the intended target.
Although the topic does get continually spun out of its original intent.

I think with most of the statements Litz makes these days they are back up by the degree of research and equippment they are using.
Like doppler radar and high speed imaging which has came a long way in the last ten years.
But who know, maybe his opinions are twisted and spun out of context.

My own comments about an increase in terminal performance come from testing Xman did that showed a difference between 1:11.5 twist barrels and 1:10 twist barrels at the same velocity with a given projectile. Ironically he also said that while most all monolithics showed a noticable increase in terminal performance the CBB's showed very little. Apparently they dont need it.

SO perhaps bolt gun from a fairly big name company with a SAAMI improved chamber and a 1:9.5 twist and an 18 or 20in barrel would help the 6.8.
It certainly wouldnt hurt. Which does twist it right back to the topic of this thread. YMMV
 

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The 6.8 SPC does not really gain a whole lot by going from a 16 to an 18 or 20" barrel. I wonder if more interest would be generated in a rifle with a 16" threaded barrel. A suppressed rifle is certainly more pleasant for hunting and for range time. I don't have a a good feel for the market, though, so does shortening the barrel with the expectation that it will appeal to people with suppressors seem like a good idea?

Ever since discovering the 6.8 SPC I have thought of it as the spiritual successor to the 30-30, and not only because the case is the same diameter. A good hunting cartridge that has relatively light recoil and works well in light, handy rifles. Heck, if Henry would chamber the SPC in a Long Ranger lever gun, the analogy would be even better.
 

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My thoughts or desire would be a short and lightweight bolt gun. 16" is plenty long enough. Under 5lbs with scope would be great. Blind box would be fine. Drop box ok as long as it fit flush in the stock. That is one think I absolutely hate about the Howa Mini Action rifles, the mag sticking out the bottom the way it does just ruins the look of the gun for me. CZ American the same thing. I had some nice CZ rifles and got rid of them because the magazines drove me nuts. Granted, it was a short ride. o_O
 

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I'm not here as much but on the Hide and barfcom, the 6.8 still has a stong hold. It usually gets attention when asking about hunting with the AR15 platform or when more power is needed vs .223. I've been using a 12.5" ARP for years as a deer rifle, a slick compact setup with a 5" can.

Cheap, full power ammo that is heavily advertised by someone like Federal or Hornady would really help but isn't going to happen soon, if ever.

I think a factory built 16" bolt gun would be cool but would have to be a Tikka for me to buy. I doubt it would sell to the masses though as 99% buy the common calibers.
 

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I don't have a a good feel for the market, though, so does shortening the barrel with the expectation that it will appeal to people with suppressors seem like a good idea?
There has been a big shift towards 10-11" 5.56 rifles in the last few years, MK18 type builds. More suppressor brands are starting to offer better flowing cans for gas guns to mitigate blow back that we normally fight with agb's, special carriers and gas tubes. One of those might be my next purchase..
 

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The whole 'twist" of this story in its intent was just to say the 6.8 does not get hampered by a change of 1:10 to 1:9
Hardly enough to initiate projectile destruction in the 6.8 or an accuracy reducing effect.
However enough to add more terminal damage to the intended target.
Although the topic does get continually spun out of its original intent.

I think with most of the statements Litz makes these days they are back up by the degree of research and equippment they are using.
Like doppler radar and high speed imaging which has came a long way in the last ten years.
But who know, maybe his opinions are twisted and spun out of context.

My own comments about an increase in terminal performance come from testing Xman did that showed a difference between 1:11.5 twist barrels and 1:10 twist barrels at the same velocity with a given projectile. Ironically he also said that while most all monolithics showed a noticable increase in terminal performance the CBB's showed very little. Apparently they dont need it.

SO perhaps bolt gun from a fairly big name company with a SAAMI improved chamber and a 1:9.5 twist and an 18 or 20in barrel would help the 6.8.
It certainly wouldnt hurt. Which does twist it right back to the topic of this thread. YMMV
Ain’t you a punny guy.😉

From what I saw, in Litz’s FB post he had a picture of something computer generated. Computer programs are only as good as the understanding of the programer and the data collected and applied. From my experience, super computers are needed when
trying to understanding gyroscopic effects. I also have no idea what Litz is using for equipment.

His only explanation when question directly was an analogy to a spinning top. To my understanding of his explanation, instead of dazzling with brilliance he baffles with BS. To this I would like to point out, that he points out, how the top returns to its vertical axis after a disruption, because of the top responding 90° to the gravitational force.

Well, the top is spinning on a vertical axis not a horizontal axis like a bullet. So, according to his spinning top analogy, our spinning bullet will tend to respond by spinning and flying nose high as it reacts to gravity during flight.

IIRC, gravitate is one of those mythical forces that he states no longer apply to spinning bullets? But, but, how does a bullet fall back to earth without gravitate? 🧐 Hummm, I wonder how he spins that phenomenon?
 

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Ain’t you a punny guy.😉

From what I saw, in Litz’s FB post he had a picture of something computer generated. Computer programs are only as good as the understanding of the programer and the data collected and applied. From my experience, super computers are needed when
trying to understanding gyroscopic effects. I also have no idea what Litz is using for equipment.

His only explanation when question directly was an analogy to a spinning top. To my understanding of his explanation, instead of dazzling with brilliance he baffles with BS. To this I would like to point out, that he points out, how the top returns to its vertical axis after a disruption, because of the top responding 90° to the gravitational force.

Well, the top is spinning on a vertical axis not a horizontal axis like a bullet. So, according to his spinning top analogy, our spinning bullet will tend to respond by spinning and flying nose high as it reacts to gravity during flight.

IIRC, gravitate is one of those mythical forces that he states no longer apply to spinning bullets? But, but, how does a bullet fall back to earth without gravitate? 🧐 Hummm, I wonder how he spins that phenomenon?
I believe Litz was using the top analogy for visualization purposes.
What he should have said is something spinning fast enough on its axis to be stabilized will return to that axis if disrupted.
Unless the gravitational force overcomes its ability to stay true to its axis. In the case of a horizontal spinning object in flight.
In the case of an artillery shell vs a rifle bullet I believe the higher arc disrupts the shell to the point where it cannot fully recover from the gravitational disruption resulting in a nose high attitude.
Where the lower arc of the rifle bullet is able to overcome the gravitational disruption to the point of staying true to its axis.
YMMV
 

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I shoot a lot of Speer 90 grain TNTs which all are run through a pointing die then meplats are trimmed, separated by weight then loaded to top of chart or over velocities worked up in my longer 1:11 barrels. This is even more prone to show when use in conjunction with a Corbin RBT-2-S rebated boat tail conversion of base in conjunction with a point form die to add rebated boat tail before trimming meplats. Why? Have discovered I can take one of the least expensive bullets available for 6.8 and in a couple or three steps have a top notch varmint bullet for reaching limits of the cartridge.

If I run these in my 1:9 barrels without reducing charge they can act a bit wonky. We are talking about a very thin skinned "varmint" bullet I have significantly altered and loaded to use on coyote from 300 to 500 yards using 18" to 22" 5R and 3R barrels. I realize when make significant changes to a bullets shape then drive it beyond chart velocity am asking for wonky so its not a complaint just an observation. A Speer 90 grain Gold Dot or most other bullets won't be as effected even when driven hard when spun up in a faster twist barrel.

I tried the 6.8 subsonic thing and just did not accomplish what I could do in a 308, 338 caliber or especially a 458 SOCOM and while often have one magazine load of 6.8 subsonic laying around very seldom even take the fast twist guns out of the vault. I will take this one out because its a great conversation starter and can.carry it concealed under a sport coat with short magazine and parted from the suppressor. Notice how much the brace has been chopped (front, back and bottom) to get the pistol short as possible maximizing the short buffer. While controllable, especially with a can this is a somewhat violent little gun.



Had one of my "massaged" 90 grain TNTs shed its jacket in the suppressor (luckily was no damage and noticed odd sound and looked through the can before shot another round) so sick to bonded bullets in this pistol build which has a lot of "non 6.8" parts that makers say 5.56 designed parts but made it 100% reliable with tuning.

 

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The 6.8 SPC does not really gain a whole lot by going from a 16 to an 18 or 20" barrel. I wonder if more interest would be generated in a rifle with a 16" threaded barrel. A suppressed rifle is certainly more pleasant for hunting and for range time. I don't have a a good feel for the market, though, so does shortening the barrel with the expectation that it will appeal to people with suppressors seem like a good idea?

Ever since discovering the 6.8 SPC I have thought of it as the spiritual successor to the 30-30, and not only because the case is the same diameter. A good hunting cartridge that has relatively light recoil and works well in light, handy rifles. Heck, if Henry would chamber the SPC in a Long Ranger lever gun, the analogy would be even better.
My thoughts or desire would be a short and lightweight bolt gun. 16" is plenty long enough. Under 5lbs with scope would be great. Blind box would be fine. Drop box ok as long as it fit flush in the stock. That is one think I absolutely hate about the Howa Mini Action rifles, the mag sticking out the bottom the way it does just ruins the look of the gun for me. CZ American the same thing. I had some nice CZ rifles and got rid of them because the magazines drove me nuts. Granted, it was a short ride. o_O

I know collectively the group here is interested in longer lengths for a 6.8 bolt gun to really boost it's performance. I get it. But the question is what would be best for the cartridge's growth, not necessarily it's current fans.

The above is what I have been saying all along. A lightweight, short barreled (respectively compared to traditional barrel lengths), handy, bolt action in the 6.8 has the potential to bring this cartridge to mainstream popularity. We all know the terminal capabilities of the 6.8, no arguments there and people just need to see firsthand it's effectiveness.

Give the world this lightweight, handy bolt action rifle with almost zero recoil and comfortable, no, a JOY to shoot for everyone. It is "normal looking" and puts North American light skinned game down like clockwork, and it could possibly become one of the fastest selling rifles/cartridges out there.

They have made these rifles in .300 BO and 7.62x39 and they have/are selling for a reason. Now, step up the game to a similar sized but higher performance cartridge.
 

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I'm not here as much but on the Hide and barfcom, the 6.8 still has a stong hold. It usually gets attention when asking about hunting with the AR15 platform or when more power is needed vs .223. I've been using a 12.5" ARP for years as a deer rifle, a slick compact setup with a 5" can.

Cheap, full power ammo that is heavily advertised by someone like Federal or Hornady would really help but isn't going to happen soon, if ever.

I think a factory built 16" bolt gun would be cool but would have to be a Tikka for me to buy. I doubt it would sell to the masses though as 99% buy the common calibers.
For me its the ammo thing. I dont do much hunting anymore but if I did I could certainly see the appeal of a short lightweight bolt gun for that.
I just think that the availability of ammo, in general is a problem. Look at the 5.56 and the saturation of the ammo market for it. I dont see people buying ar-15's the way they have without that surplus ammo market. I think what Im saying will play out in the car market soon. When gas is so expensive only the people who are able to own private jets and fill them up will be able to do the same with a gas powered car. Why buy a gasoline powered car if you cant afford to fill the tank? Same with a firearm, lets but that gun because we cant get any ammo for it.
 

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Having a very organized repository of information, particularly the gov. caliber studies and original testing on 6.8 SPC would help when people make arguments for why 5.56 is "enough" or why there is a reason to use 6.8 SPC aside from just hunting. When it comes to AR's, it's not the hunting community that drives a cartridge to success, it's the 2nd Amendment community focused on Home Defense, SHTF and defending against gov. tyranny or being prepared to resist foreign invasion. I think there's a lot more hunters across the US using bigger caliber bolt guns than hunters using ARs/M4's, although it's gaining popularity for medium game because of viable cartridges like 6.8 SPC. Everyone I know in my home state of WI uses .308, 30-06 etc. for Deer, 12ga for turkey. Maybe some use lesser cartridges for coyotes including 5.56.

And, as BillB said, ammo is a big problem. Back when first got into 6.8 SPC, I could buy a 200rd can of 110gr Hornady OTM at $0.59 a round and it outperformed every 5.56 load out there costing $1-$1.50 a round. Sure, 5.56 FMJ is cheap and was $0.30 per round range back then, but anything you would use for hunting / duty was 2x-3x cost with less performance.

S&B has a bunch of 110gr FMJ that shoots well now, but it's still $0.90~$1 a round and anything not FMJ in 6.8 is at least $1.50 a round. I don't see the slightly larger case, bullet, powder costing double so it's obviously a volume issue. Volume can be solved by awareness and support from ammunition suppliers, so until the ammunition issue is resolved I see this being a niche cartridge. And I will not get rid of my 5.56 just in case 6.8 ammo production were to cease all together under really bad conditions. I will always go to my 6.8 over my 5.56 as long as I have ammo for it, but that's the big question!

Druid Hill makes great SPC II spec ammo for ARP and SPC II chambered barrels. The problem DHA has is getting components to even make it.
 

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BTW Underwood also makes 6.8 SPC loaded with the VMax bullet (their version of Hornady Black). I just saw that a few months ago when buying some Leigh XD 90gr 9mm ammo after reading ViperSystems terminal performance reports on the XD bullets (outperformed ALL hollo points with zero failures). Maybe a collection of ammo suppliers for 6.8 SPC would be helpful as well.

6.8mm Remington SPC 110gr. V-MAX® Lead core with Copper Jacket Hunting Ammo (underwoodammo.com)

I personally am a supporter of this cartridge over any other cartridge that fits into an M4 package not because of anecdotal stories (although they do factor in and cannot be outright dismissed), but because of the combination of both actual testing / data over tens of thousands of test loads, countless studies performed by DoD and it's various associated branches combined with the hunting successes. It's the aggregate of information and that's what I use to help inform others.

I think Vortex hit the nail on the head, it was NEVER 6.8 SPC's actual performance that was the issue. It was the timing, lack of awareness, inaccurate information, the botched cambers etc. and over hype that hurt it's adoption irrespective of how well it actually performed for its role from 0-400~500 yards (combat) or 0-300~400 (hunting).
 
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