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File 156222159421.jpg - (75.55KB , 609x667 , image-863.jpg )
109075 No. 109075 ID: b2b3ad
http://soldiersystems.net/2019/06/19/us-army-ngsw-submission-6-8-sherwood-by-vk-integrated-systems-and-bachstein-consulting/
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>> No. 109076 ID: 9dcda2
>>109075
Nothing the Army will ever take seriously.
>> No. 109077 ID: eb9dbe
>6.8mm

When will this meme die.
>> No. 109078 ID: 48ddd0
File 156228938014.jpg - (1.89MB , 2560x1440 , Vanquish laser cannon.jpg )
109078
>>109077
When death-rays make these bullet-sprayers obsolete.
>> No. 109081 ID: b2b3ad
>>109077
Why is it always 6.8mm and not just 6mm? I thought 6mm was inherently better for ballistics. I dunno how they want to penetrate modern ceramic plates with anything that a grunt can reasonably carry tho.
>> No. 109082 ID: 9dcda2
>>109081
Bigger bullet for more mass.

https://thebiggamehuntingblog.com/6mm-creedmoor/

> consider the supersonic ranges of the three cartridges. This particular .243 Winchester load drops below the speed of sound around 1,150 yards, but the 6mm Creedmoor stays supersonic out until around 1,375 yards and the 6.5 Creedmoor doesn’t cross the sound barrier until around 1,450 yards.

6.5 CM will stay supersonic longer and is less affected by wind. But as always, everything is a compromise. 6.5 CM is a good tradeoff between velocity, bullet weight, ballistic coefficient (BC), felt recoil, and barrel life. You can drive a bullet faster with a super bottlenecked cartridge, but it will burn out barrels.

> I dunno how they want to penetrate modern ceramic plates with anything that a grunt can reasonably carry tho.

Yeah, then there's that problem. Although new types of bullets may do a better job.

https://www.israeldefense.co.il/en/node/32911
>> No. 109083 ID: b2b3ad
>>109082
>6.5 CM will stay supersonic longer and is less affected by wind. But as always, everything is a compromise. 6.5 CM is a good tradeoff between velocity, bullet weight, ballistic coefficient (BC), felt recoil, and barrel life. You can drive a bullet faster with a super bottlenecked cartridge, but it will burn out barrels.

That's still 6.5 and not 6.8 tho, why does the Army want 6.8 specifically? And why enlarge the diameter and not make the bullet longer? Would help with sectional density too.
>> No. 109084 ID: 9dcda2
>>109083
> That's still 6.5 and not 6.8 tho, why does the Army want 6.8 specifically?

That I don't know. I used 6.5 CM as an example because it's really popular and I've shot it like twice. (I'm not a PRS guy.)

> And why enlarge the diameter and not make the bullet longer? Would help with sectional density too.

6.5 CM already has really long bullets and still fits into a .308 overall length.
>> No. 109085 ID: 6affc4
>6.5 CM already has really long bullets and still fits into a .308 overall length.

Yeah, you're right, probably due to geometry.

>https://www.israeldefense.co.il/en/node/32911

What's the trick with these? Carbide core?
>> No. 109088 ID: 8e4d38
>the XR-68 houses the SmarTak electronics system, an advanced weapons system design for real-time battlespace awareness.
Sounds kind of like the dozens of fancy looking eyepro mounted HALO HUD doodads I helped the armorer do a layout on the other week.

>we want the best inovative tech out there
>Nobody knows how to use it and it's expensive
>let's throw it in a box and only bring it out to count every change of command and then probably lose the cables when putting it all away time fucking now due to some absurd time hack
Army strong
>> No. 109171 ID: eb971f
>>109076
>Nothing the Army will ever take seriously.
This. The Army is moving toward a plastic cased ammunition for their next generation of rifles and LMGs so this is already dead in the water. It also doesn't do anything better than an AR in 5.56 as long as the barrel is at least 16 inches. You only run into problems with that cartridge and bullet when the barrel is chopped off. I am so sick of tards who fuck up a perfectly good, well-engineered product then either complain that it's badly designed or try to come up with a "fix" that is anything other than undoing their bubba-fudd hackjob.
>> No. 109271 ID: 0d01d8
>>109083
>why does the Army want 6.8 specifically?

Just an educated guess here. The reason they went full retard for the 6.8 SPC is the impressive performance--in ballistic gelatin, anyway--of a non-catalogued prototype 115gr .270 caliber Sierra MatchKing bullet that someone at Sierra was nice enough to load into some test ammunition for the Big Army circa 2002. Supposedly in tests they were highly impressed by its consistently rapid yaw cycle.

Which is weird because the conventional wisdom is that "fleet yaw" is a problem because yaw cycle is pretty random and inherently inconsistent and can't be affected greatly by bullet design or velocity, it just is what it is. (.303 British Mk. VIIz and 5.45mm 7N1 say "'sup?" I know, guys. I know.)

Nonetheless, the performance of two or three, max, of these Sierra bullets in Jello blocks made the Big Army's eyes bug out, back when they were still wedded to at least paying lip service to the Hague Convention, which the US never signed in the first place. Whether this level of performance could be sustained even in principle with ammunition using bullets that weren't basically handmade toolroom prototypes, I do not know.

I personally think there's no reason for the 6.8 SPC to exist. 6.5 Grendel does everything it purports to do, but better, with flatter trajectory and better retained velocity that, with carefully chosen bullets, (supposedly) catches up with and surpasses 7.62x51 NATO in terms of kinetic energy somewhere around 1100-1200m, and the high sectional density of 6.5mm bullets allows it to catch up with 7.62 in things like penetrating sandbags and wooden planks long before then. Of course, both 6.8 SPC and 6.5 Grendel are both MUCH heavier, round for round than 5.56mm, allowing the guys at the sharp end to carry less ammo for the same weight, and being MUCH more powerful than 5.56 also means they're MUCH less controllable in full auto fire, and these were the exact problems 5.56mm was created to solve 55 years ago.

You'd think, though, that if the Big Army were serious, and not just fucking around with taxpayer money to give Special Forces new toys to make them feel more special, they'd convert the SAW or whatever its replacement is to the new caliber first and foremost, right? Because in modern fire-and-movement infantry tactics the SAW is the infantry squad and platoon's real teeth, the riflemen are just there to keep the SAW gunners from getting outflanked and overrun, amirite guise? So they'd either create a replacement for 5.56mm that fits in SAW links or design a new link and a SAW replacement around it, but almost 20 years on, exactly jack and shit have been done on those fronts.

tl;dr 6.8mm cartridges are a Big Army bad idea just like UCP "camouflage." They could switch to 6.5 Grendel, I suppose, but it isn't magic either, and there are serious tradeoffs that have to be seriously considered, in terms of range and power vs. ammo weight and full-auto controllability.

There really wasn't anything wrong with 5.56mm, just like there really wasn't anything wrong with M81 Woodland cammies or "chocolate chip" desert camouflage, but the big boys with the big budgets just have to have their dickwaving contests.

And I say this as someone who really wants to like Multicam, or Scorpion, or whatever the fuck the Big Army is calling it this week. And I really want to like the 6.5 Grendel, too--a store near me has one of the new Ruger compact bolt-actions and I am thinking hard of getting one to be a lightweight long-range range toy bolt gun.


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