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Negative. The 6.8 NGSW rounds are not 6.8 SPC variants. They are larger, more powerful cartridges. The only thing they have in common with 6.8 SPC is bullet diameter.
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You clearly misread what I stated. I did NOT state they were all 6.8 SPC variants. I stated that "they were all variants of 6.8. <-----(see the period) Just not SPCII".
 

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My understanding is that the 3 rounds in the running are all variants of the 6.8. Just not the SPCII.
They are all using bullets in .277 in dia. about the only thing they have in common is the bullet and a primer. US Army dictated the bullet the weapon was to be designed around. GD uses Polymer cased ammo and a bullpup design with longer barrel to achieve the goal. Textron uses telescopic cased ammo (seems a little to complex to me) and a standard looking rifle. Sig is basically a 308 case necked to .277 with a Steel case head and brass body. They use high pressure to achieve the goal, 3000fps with 16" barrel and what looks like an M4 style design. I'm personally pulling for sig, who has already released the rounds to civilian market as the 277 fury in a bolt gun. Sig design would also allow for 308 surplus to be fired in the same rifle with just a barrel swap and it is the most traditional style of the three entries.
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SIG

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They are all using bullets in .277 in dia. about the only thing they have in common is the bullet and a primer. US Army dictated the bullet the weapon was to be designed around. GD uses Polymer cased ammo and a bullpup design with longer barrel to achieve the goal. Textron uses telescopic cased ammo (seems a little to complex to me) and a standard looking rifle. Sig is basically a 308 case necked to .277 with a Steel case head and brass body. They use high pressure to achieve the goal, 3000fps with 16" barrel and what looks like an M4 style design. I'm personally pulling for sig, who has already released the rounds to civilian market as the 277 fury in a bolt gun. Sig design would also allow for 308 surplus to be fired in the same rifle with just a barrel swap and it is the most traditional style of the three entries.


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While I like the 6.8 I have two questions for ALL of the applicants in the running. (1) What kind of recoil is involved and is there some type of recoil mitigation involved? and (2) What kind of barrel life is anticipated?

I am sure that these questions have been addressed as they are important considerations.
 

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You clearly misread what I stated. I did NOT state they were all 6.8 SPC variants. I stated that "they were all variants of the 6.8. <-----(see the period) Just not SPCII".
Hmm. Everyone else on 68forums whom I have seen type "the 6.8" by itself, was using it as an abbreviation of 6.8 SPC.
If you did not mean the 6.8 NGSW candidate rounds are variants of 6.8 SPC, to what 6.8 cartridge were you referring?

P.S. I'm pretty sure that SPCII is a chamber configuration, not a cartridge. At least, I have never seen 6.8 SPCII ammo.
 

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Recoil is said to be soft (probably not 556 soft but less than 308 is how I innferred), all rifle having a can helps also. I would say barrel life would be similar to 270wsm since that's the same level of performance just in a 16 in barrel instead of 24.
 

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[video=youtube;bL1wF-nCGc4]
If they can keep the pressure down, and just do a barrel swap, they should definitely have a leg up. Even if they dont get adopted as the primary weapon, the ability to retrofit existing weapons will be a big boost for them.
 

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The "normal" chamber pressure of this cartridge is the reason that the General Dynamics/True Velocity NGSW submission is bullpup design. That is the only way that they could meet the velocity specs and still keep the overall length down. At least their cartridge is lighter than the existing 7.62x51. The Sig round appears not to be. As near as I can tell, the weight savings that Sig claims is against a fictitious, significantly larger conventional cartridge that could provide the same performance out of short barrels.

It is entirely possible that True Velocity decided to play the "long game" on ammunition by figuring that even though they might lose the NGSW competition with a bullpup, there would be a good chance that their ammo would be more widely fielded in rebarrelled existing weapons.
 

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Read like the selection was made but the link was old.

Sent from my SM-G973U using Tapatalk
There have been a couple of articles like that. In the end, they have really meant: "our cartridge has been CHOSEN (to be one of the candidates)." As far as I know, no selection yet.
 

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I think that having melonited barrels is going to be part of the equation for barrel life. That may achieve something similar to normal 5.56 barrel life from the much higher pressure cartridges.
 

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I watched two Youtube videos of recent journalist encounters with the Sig and Textron 6.8 rifles. Very interesting.

The Sig "Spear" is very conventional, except for the cartridge, which is a 7.62 Nato with a steel case head, necked to .277 and loaded to 90k psi. Makes you wonder about barrel life, an issue which the Sig employee avoided. Bare rifle weighs 8 plus lbs, recoils about like a Garand.

The Textron was the more interesting of the two, with its moving chamber, revealed via very thorough coverage of a field strip. Makes you wonder about accuracy, an issue the Textron employee avoided. Looked to be lighter than the Sig and with all the moving parts, perhaps less felt recoil. This is the one with the all plastic, telescoped ammunition. As a reloader I hate it, but very interesting from the Army's POV.

The third contender, General Dynamics, doesn't have a recent demo on YouTube, but stay tuned. Its the one that fires the True Velocity plastic ammo in a bullpup rifle. If I see something recent, I'll relay it here. BTW, attempts to fire any of these 9-pound 6.8 service rifles full auto is comical to watch. Reminds me of the attempts at full auto in the M14 some 60 years ago, a complete waste of time.

Sig

Textron
 

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... psi. Makes you wonder about barrel life, an issue which the Sig employee avoided...
Still nothing on Bartlein's MOD400bb? That is a thread with Frank Green from Bartlein talking about it.

Re Melonited, I am curious about both that, and cryro-treatment with the new alloy, and if it helps with accuracy and barrel life.
 

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I think that the requirement for barrel life is 10,000 rounds. The Sig is using a fairly exotic "maraging" steel, which is much tougher than what is normally used for barrels. I don't know if they use chrome lining or not. My understanding is that chrome still provides better barrel life than melonite. Melonite is cheaper and often provides better accuracy, though. The maraging steel may well be stronger than either of these coatings.
I know that there has been significant research into "super alloys" for barrels for a number of years, but I don't know how close that is to production.
 

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Still nothing on Bartlein's MOD400bb? That is a thread with Frank Green from Bartlein talking about it.

Re Melonited, I am curious about both that, and cryro-treatment with the new alloy, and if it helps with accuracy and barrel life.
I saw that thread on the hide and Frank G had mentioned he sent 2 barrels to the Army in 300wm. IIRC, went more than double on barrel life.
 
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I watched two Youtube videos of recent journalist encounters with the Sig and Textron 6.8 rifles. Very interesting.

The Sig "Spear" is very conventional, except for the cartridge, which is a 7.62 Nato with a steel case head, necked to .277 and loaded to 90k psi. Makes you wonder about barrel life, an issue which the Sig employee avoided. Bare rifle weighs 8 plus lbs, recoils about like a Garand.

The Textron was the more interesting of the two, with its moving chamber, revealed via very thorough coverage of a field strip. Makes you wonder about accuracy, an issue the Textron employee avoided. Looked to be lighter than the Sig and with all the moving parts, perhaps less felt recoil. This is the one with the all plastic, telescoped ammunition. As a reloader I hate it, but very interesting from the Army's POV.

The third contender, General Dynamics, doesn't have a recent demo on YouTube, but stay tuned. Its the one that fires the True Velocity plastic ammo in a bullpup rifle. If I see something recent, I'll relay it here. BTW, attempts to fire any of these 9-pound 6.8 service rifles full auto is comical to watch. Reminds me of the attempts at full auto in the M14 some 60 years ago, a complete waste of time.

Sig

Textron
The guy shooting the SIG ... LOL Leaning back shoulders behind hips may work for highpower comps but not auto fire.
 

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10,000 rounds at that kind of pressure?

Never say never. Still I can't wait to see what rabbit gets pulled out of that hat. Going to be interesting.

Technology is definitely advancing. I don't know what its called, or how it works exactly but I heard of a different way to get Chromium or Chrome into the outer layer of metal instead of just on it. Accuracy was theoretically going be better. Tried a search for it, didn't find anything.

Obviously going to be a combination of things. I looked into cryogenic treatment for some stuff I already have. Pretty sure I want to know more about it, and Bartleins MOD400bb too.
 

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Here is the last of three recent YouTube videos reviewing the several NGSW 6.8mm rifles, this time its the General Dynamics submission with its True Velocity polymer case ammo (6.8x51mm). Its the bullpup design with the shorty suppressor, manufactured by Beretta. I'm starting to warm up to GD's design, the reviewer liked it well enough. Both the rifle and companion AR have a reciprocating barrel, which raises questions about accuracy. While we have have recent, closeup looks at each design and can watch them in motion, the Army is keeping mum about how each is performing in the field with our GIs, especially re accuracy, durability, etc.

Originally, I was concerned about GD's SAW replacement that feeds only from magazines, with no QC barrel, sort of a modern BAR. Now, I'm warming up to the idea of a light, fast rifle squad having one or two of its service rifles equipped with longer, heavier barrels and bipods for fire support, backed up by a platoon-level weapons squad with traditional GPMGs that fire the same 6.8mm ammo as the rifle squad. Same for the coax MGs on supporting tanks and other armored vehicles. This will greatly simplify the small arms ammo situation in US Army maneuver battalions. - CW

 

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I watched the trigger pull in semi....that looks like a long trigger pull. trigger has always been a complaint on the bull pups I've shot like the AUG and Tavor.
 

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I’m curious what’s the fastest muzzle velocity anyone has gotten here with a 135gr pill in a 20” barrel. Seems like a lot of money for 3-400 more fps
 
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