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Sig's web site has the Elite 150gr Bonded pegged at 2830 FPS for a 16" barrel which is blazing fast for that barrel length and weight. 2667 ft-lbs muzzle, similar to 270 Win performance from a 24" barrel, but the 270 Fury is doing that from a 16" barrel. @ 700 yards it is still cooking along at just a tick under 1700 FPS @ 958 ft-lbs. BC is listed at .500. Chamber pressure is around 80k PSI, hence the hybrid cartridge design, massive bolt lugs and new platform.

For a 13" barreled MCX Spear with integrated suppressor, no sights, lights, optics, it clocks in at 8.4 lbs, pretty heavy compared to a 6.8 SPC chambered M4.

6.8 SPC would have enhanced a fire teams capabilities at the same ranges as 5.56 NATO is used, but it clearly doesn't provide the long range capability for the mountains of Afghanistan nor does it provide armor penetration beyond 100 yards, so I get why a full powered cartridge was developed capitalizing on 6.8mm bullet's balance between terminal performance and exterior ballistics.

While this will never happen, the most ideal solution in my opinion would have been to adopt 6.8 SPC to replace all 5.56 NATO chambered M4A1's for applications intended for 5.56 NATO and then develop / adopt the new 6.8x51mm full powered cartridge / NGSW platform for DMR and Squad Automatic roles which augment a fire team's capability.

A fire team could theoretically be comprised of three 6.8 SPC M4's with one XM5 (rifle variant) or one XM 250 (machine gun variant). Alternatively, you could equip two team members with 6.8 SPC M4's, one with an XM5 and one the XM 250.

It's just a shame 6.8 SPC was passed over in favor of the M855A1 load in 5.56 NATO because it still does everything 5.56 NATO does, but much better. And they could have used the same projectile design of M855A1 or the now defunct MK318 scaled up for 6.8 SPC just like they did with M80A1.
 

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Sig's web site has the Elite 150gr Bonded pegged at 2830 FPS for a 16" barrel which is blazing fast for that barrel length and weight. 2667 ft-lbs muzzle, similar to 270 Win performance from a 24" barrel, but the 270 Fury is doing that from a 16" barrel. @ 700 yards it is still cooking along at just a tick under 1700 FPS @ 958 ft-lbs. BC is listed at .500. Chamber pressure is around 80k PSI, hence the hybrid cartridge design, massive bolt lugs and new platform.

For a 13" barreled MCX Spear with integrated suppressor, no sights, lights, optics, it clocks in at 8.4 lbs, pretty heavy compared to a 6.8 SPC chambered M4.

6.8 SPC would have enhanced a fire teams capabilities at the same ranges as 5.56 NATO is used, but it clearly doesn't provide the long range capability for the mountains of Afghanistan nor does it provide armor penetration beyond 100 yards, so I get why a full powered cartridge was developed capitalizing on 6.8mm bullet's balance between terminal performance and exterior ballistics.

While this will never happen, the most ideal solution in my opinion would have been to adopt 6.8 SPC to replace all 5.56 NATO chambered M4A1's for applications intended for 5.56 NATO and then develop / adopt the new 6.8x51mm full powered cartridge / NGSW platform for DMR and Squad Automatic roles which augment a fire team's capability.

A fire team could theoretically be comprised of three 6.8 SPC M4's with one XM5 (rifle variant) or one XM 250 (machine gun variant). Alternatively, you could equip two team members with 6.8 SPC M4's, one with an XM5 and one the XM 250.

It's just a shame 6.8 SPC was passed over in favor of the M855A1 load in 5.56 NATO because it still does everything 5.56 NATO does, but much better. And they could have used the same projectile design of M855A1 or the now defunct MK318 scaled up for 6.8 SPC just like they did with M80A1.
Funny thats exactly what the guys on the MAC channel said when they were discussing it
 

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6.8x51?????? I don't get it. What is the theoretical benefit of this cartridge over the 7.62x51???? We already have the tooling to make AR10 rifles in 7.62x51 so why spend hundred of millions of dollars to purchase a new cartridge and weapon platform that does the same thing as ones on the civilian market. Higher pressures in the cartridge seem to be a recipe for higher failure rates on parts and barrels. It is also heavier than current combat loads. Less ammo for the weight? I agree with others that the 6.8SPC would have been a better short term solution; and one which would have been cheaper to field than this R&D mess. I have thought that a 6.8x47 or 48 size round would have been a good compromise. A little longer action, but not as big as the AR10. Apparently the DOD does not believe that all combat rifles are a compromise between weight, serviceability and lethality. Not every cartridge excels in every environment. But, I am just an old retired sailor, so WTH do I know...
 

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In my opinion it's the stupidest round ever. Seriously? A 3 pc. round? Sue it's got a lot of pressure. But the cost! Look, I'm all for our men and women in the military having the best there is. But come on! And what, there wasn't an American gun manufacturer they could have given American taxpayer money too? And yes, I know. Sig has Sig USA. But they had to do that in order to bid on and get government contracts. But in the end, they're a German company! And to have to rely on some other country for your needs? What happens if things go bad?

Lastly, the M4 platform could have been modified and customized into one of many great cartridges already out there. The 6.8SPC for instance? The 6.5 Creedmoor? The 6.5 Grendel? Or hey, how about the .308?

And the recoil as mentioned in the video? May as well gone with .308!

Rant over!
 

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It's about maximum fire power and performance in the most compact package possible to provide over match to existing and emerging threats. Existing threats are full caliber long barreled DMR's and Machine guns in 7.62x54R, the Chinese equivalents etc. and emerging threats is new body armor technologies and the wider use of existing body armor (although, as I mentioned, there's a lot of areas that if hit by modern ammunition result in complete neutralization that body armor doesn't cover, the military sees it differently, in that they need to shoot through the armor, not around it).

1. 7.62x51mm CANNOT achieve velocities necessary for body armor penetration at intermediate ranges without using long barrels in the 20-24" range. That may be ok for open country, but it's not when riding in vehicles, air craft or other modes of operation. It's also difficult to use in CQB or urban areas.

2. 7.62mm projectiles will ALWAYS be pushing a larger volume of air out of the way as they travel to their target. Exterior ballistics matters just as much, but not more than, terminal performance. Exterior ballistics favor longer skinnier projectiles. Terminal performance favors larger diameter projectiles. Air is a gas and gasses follow the properties fluid dynamics, thus bullets that are aerodynamic require higher velocities just to achieve a minimal level of expansion and significantly more velocity to achieve the same expansion as larger diameter projectiles. If they slip through the air well, they slip through soft tissue just as well, so you have to compensate by driving them faster to achieve the same drag forces on impact. All projectiles are a balance between Exterior and Terminal, 6.8mm does it better for combat applications than 7.62mm or 5.56mm, kind of two extremes.

Basically they are giving you the performance of a 24" barreled 270 Winchester deer rifle out of a 16" barreled suppressed select fire HK417-Like rifle (short stroke piston). To be clear the XM 5 (MCX Spear) is NOT an AR-10 or HK417, but it does share many AR-like features in it's form factor and controls placement / operation.

In order to penetrate armor, you need mass, velocity and maximum force per square inch. You simply can't get the velocity necessary to penetrate armor at extended ranges (300 yards +) from a 13-16" barreled 7.62x51mm. They also have massive blast and flash, so you really need to suppress full caliber short barreled weapons to make them usable without blowing your buddies eyes out or having a giant 4th of July fire works display with every shot in low light.

The MCX Spear + 277 Sig Fury give you all of that performance in one package that weights about the same as a 16-18" barreled AR-10 or HK417. Sometimes, there's just no replacement for displacement. Period.

But I still hold to my argument that 6.8 SPC fulfills the roles of 5.56 NATO far better than 5.56 NATO, with the ideal solution, barring logistics and politics, to be 6.8 SPC for all applications where 5.56 NATO is used and 277 Sig Fury for all applications 7.62x51mm is used.

Instead they opted for keep 5.56 NATO because of logistics / geo politics and settle for improved 5.56 ammunition and then field 277 Fury for an over match to other similar threats and as an option to scale up and replace more 5.56 with 277 Fury in the event a foreign adversary fields a modern military equipped with body armor.
 

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But, I still contend that body armor is a mixed bag even with all of the modern technology. I know, I have a pair of Hesco U210 plates, $700 each. 3.9 lbs per plate, less than 1/2 in thick, multi-curve, shooters cut. Maximizes mobility, minimizes weight and bulk while offering protection against special threats like the newish M855A1.

BUT, in training, I don't feel like I'm bullet proof. Some guy on full auto could just pepper me and get hits in my shoulders, neck, face, head, thies, abdomen or pelvic region and I'm DONE. Or any lateral (side) shot, because I only run soft armor on the sides and the hard armor side plates offer VERY LITTLE coverage and inhibit mobility.

Regardless of how good the armor is at stopping bullets, it doesn't cover enough of the body to make you a walking tank, not even close and any skilled shooter can adapt to using a modified doctrine of 1 or 2 in the chest to disorient, 3 to kill / disable by a hit to an unprotected area. With low recoil cartridge's at CQB distances it's perfectly workable. And at extended ranges, precision shots can just circumvent protected areas all together (aka taking a precision shot on a target's unprotected area who isn't aware your there in an ambush).

The other issue with going through armor is that ANY AP load that penetrates the armor is going to Ice Pick, your not getting an expanding projectile through the armor that creates wounds 5x the size of the projectile. And the penetrator core is smaller than the bullet diameter which reduces it's effects further. So an AP round in 277 Fury, .308 or any other full caliber is still half the diameter of 9mm ball ammunition. It's like shooting someone not wearing armor at close range with handgun ball loads....lethal if in the right spot (aka shot placement, penetration depth), but far from ideal with non-vital hits.

That should tell you how ineffective 5.56 AP is, 5.56 is already a small diameter bullet and the AP penetrator is even smaller. With larger calibers, at least the AP core may be as big as the 5.56 bullet and act like an ice picking M855. That's when volume of fire or shot placement become critical.

Either you hit the CNS/Heart/Liver with non-expanding penetrators to take down the target or you kill them with volume of fire (many small holes equal one big one). My argument has been that enemy combatants may be just as effective to place one shot in the chest to the armor to disorient and damage the target (broken ribs, wind knocked out of them), then place another shot or several shots on unprotected areas to disable / kill.

Think about VMax hitting an enemy soldier in the throat, neck, T-box, shoulder, femoral artery, pevlic region....they aren't getting back up. You will literall blow fist sized holes in arteries and limbs or the gut (extraordinarily painful). That's no different than 5.56 doctrine now of two in the chest, one in the head for a failure to stop due to the failures of M855.

So I see 6.8 SPC as low enough recoil you can still shoot fast, bring more energy to an armor plate center mass hit to disorient then finish off with hits on unprotected areas at CQB distances. That's kind of what US soldiers adapted to in order to compensate for M855's failures, it may be re-adopted to defeat armored threats without AP ammunition which has very marginal terminal performance after penetrating the armor in any caliber, but especially in 5.56.

I really don't think 277 Fury is going to produce significantly better terminal performance after penetrating armor, so it's likely multiple center mass hits would be needed or a single center mass hits with follow ups to unprotected areas. I predict the wide spread use of armor is going to necessitate a return to marksmanship and tactics even with technology.

There's no perfect armor just like there's no perfect bullet.
 

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I guess we've gone full circle: everyone thought the Army was stupid when they adopted the M-16 and 5.56, and now everyone thinks the Army is stupid for moving away from it.

Last week I spent a day on a long distance range with an instructor as I'm looking to get into PRS. It was really the first time I've shot much beyond 400 yards. It was eye opening for me in that with a good rifle, ammo, glass, and ballistics computer, I was amazed at how quick and easy it was to get hits on targets out to, and past, 1,000 yards. When the M16 came out, that long range capability was reserved for hand crafted weapons and weeks long special training. I also just received my Bluetooth enabled laser rangefinder yesterday. I can connect it to my Kestrel 5700, lase a target, and immediately get my Elevation/Windage in both my LRF and my Kestrel - it's sweet. The NGSW puts all that, and more, on top of the weapon, while displacing other components that are already mounted to the beloved M4 (e.g., ACOG and PEQ-15). The technology / capability has come a long way and, from my perspective, NGSW will put that capability in hands of troops and more than double the effective range of every rifleman. I think NGSW is a smart move and I'm all for the Army getting out in front and equipping soldiers with "overmatch" capabilities before we enter the next war.

ThELioN70x7 did a good job of explaining why the 6.8x51 is needed to deliver the overmatch capability, so I'll leave that alone except to remind folks the M5 only has a 13" barrel, will be suppressed and still deliver superior lethality over the 7.62x51. It makes an SR-25 with a suppressor look like Brown Bess. I think the Army already had a bullet in mind and knew how fast they had to push it to get the results they were looking for and made that the requirement.

I will admit that I'm surprised that the Army plans to field this universally, but it makes sense given logistics and the fact that Iraq taught us that battlefields are no longer linear and even support troops often find themselves in engagements. I partially suspect M4s might be hard to pry out of the hands of REMFs and end up kind of like the M1 Carbine of WWII, but regular Army troops don't get a vote in their MTOE. And SOCOM guys will always have access to an armory full of all sorts of stuff and will choose the right weapon for the mission.

I watched that MAC video last night and I couldn't keep from thinking how much it reminded me of old ladies sitting around in a knitting circle.
 

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Hmm, I'm not sure if the Army really expects or needs the round to penetrate or just deliver enough energy to sufficiently deform and still incapacitate.
Armor penetration capabilities were one of the primary requirements behind the velocity, diameter and mass specifications. They desire to be able to defeat all modern body armor and all body armor expected to be developed over even the next decade by peer adversaries, something 5.56 cannot or will not ever do and neither can 6.8 SPC or other medium calibers except at closer ranges, out to about 100 yards or less, they can defeat existing Level IV.

Here's a list of requirements that were publicly announced (paraphrased):

1. Armor penetration at extended ranges against all current Level IV and planned future armor for the next 10 years.

2. Superior exterior ballistics AND terminal performance compared to 7.62x51mm M80A1 LAP and long range loads (which have inconsistent terminal performance at CQB distances and issues with barrier blind)

3. Signature reduction (flash, blast, sound)

4. Weight requirements to fall in line with existing interim solutions like HK417 chambered in 7.62x51mm (known as M110A1)

5. Overall system size / dimensions similar to the M110A1

6. Cartridge to fire 135gr government provided 6.8mm projectile at approximately 3,000 FPS. Said projectile is a 277 caliber scaled up variant of the M855A1 bullet (which was also scaled up to 7.62 for the new M80A1 load). What will they call this, maybe a M277A1 (just a wild guess).

7. New optics package to deliver ballistics compensation to increase the probability of a 1st round hit at extended ranges. Variable magnification from 1x to 8x with Red Dot capability for CQB. Basically they specked out an LVPO with a ballistics computer on it as the primary optic.

There's really three components needed, the cartridge, the rifle and the optics package. They delivered all three between two companies, Sig and Vortex. Sig already supplies the M17/18 P320 based hand guns. Vortex is a contract supplier for some Marine Force Reconnaissance units that use the Razor HD Gen II-E's.
Wood Font Glass bottle Ammunition Art
 

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BTW this system belongs in the hands of every family man in America. A nation of razor wire topped with a crown of thorns. Come screw with America and find out what happens. We don't need to be the world police, but we do need to maintain peace at least as far as our nation is concerned through superior fire power. Boots on the ground is still to this day the way you control an area despite all the fancy toys.

No other nation has anything remotely similar to this capability. The optics alone, which will become available to the public as it's not a prohibited item, would really do the trick as it can be used on any existing platform. Imagine the new combat optic on 6.8 SPC chambered AR-15's or AR-10's in the still venerable 7.62x51mm or 6.5 Creedmoor.

It would accurize 5.56, 6.8 SPC, 6.5 Grendel, 7.62x51mm and a variety of other platforms and cartridges even if they do not have the extended range capabilities of 277 Fury using 16" barrels. Of course you could run longer barrels with existing calibers to come close to 277 Fury as well, for open country that would probably work just fine.

There's a lot of bolt guns, AR-10's, M1A's in 7.62x51mm that can still hit out to 800+ yards, some in 300 Win Mag, 6.5 Creedmoor etc. In my opinion the optic is the real game changer because it revolutionizes long range shooting for any person with good fundamentals, is entirely made here in the US of A and can be utilized with any platform that has a standard PIC rail on top.
 

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The real trick is range estimation. Wind is important but workable with hold offs. I'll be shooting an AR-10 in our 600yd long range match tomorrow as an AR-T. Cleaning the 600 yard target is pretty easy. Getting hits on even a head sized target at 600-800 yards with a cartridge with the ballistics of the 6.8x51 would be fairly easy IF you knew the precise distance. That will be the key to using the optics. Getting a precise distance and holdover.
 

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The real trick is range estimation. Wind is important but workable with hold offs. I'll be shooting an AR-10 in our 600yd long range match tomorrow as an AR-T. Cleaning the 600 yard target is pretty easy. Getting hits on even a head sized target at 600-800 yards with a cartridge with the ballistics of the 6.8x51 would be fairly easy IF you knew the precise distance. That will be the key to using the optics. Getting a precise distance and holdover.
Not sure if you're making the point, but the NGSW puts a laser range finder right on top of the optic which also calculates and presents the E/W solution within the optic.
 

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There is already a 6.8 SPC round that will defeat NIJ 4 rifle plates at 200 meters made in the USA. Its just not sold in the U.S. as company making it says it costs too much money to get anything through U.S. military trials so they sell it overseas. They have a 7.62x51 round that extends NIJ 4 failure to nearly 300 meters and a 300 Win Mag to 500 meters. Copper pre-fractured bullet with tungsten core sou the copper expands violently when hits water based medium like human or animal flesh, is barrier blind and when his armor it just keeps drilling through. I scored some test rounds in 5.56, 6.8, 308 and 300 Win Mag but was under the agreement could not release photos or velocities but it will never be something discussed much on our side of the pond as it does to within 80% the 277 Fury does in a M4 chassis.
 

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There was a grendel fan boy in the comments claiming it could penetrate level 4 body armor at 300 yards lol
Yeah I just came from another forum where dudes are drooling over the Grendel telling me it can defeat lvl IV plates. I've never seen evidence of this. Anybody have videos?

Sent from my Pixel 3 using Tapatalk
 

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Yeah I just came from another forum where dudes are drooling over the Grendel telling me it can defeat lvl IV plates. I've never seen evidence of this. Anybody have videos?

Sent from my Pixel 3 using Tapatalk
Unless they have some AP bullets pulled from some country that once used a 6.5 in the military I doubt it. First off the G doesn't push any bullets fast enough to do it.
 
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