Textron Systems NGSW Rifle and LMG

[JASmith]

Since 6.5mm offers zero improvement in ability to penetrate body armor, zero reduction in bulk of gun or ammo, and zero increase of magazine capacity, why spend the time and $$$ to switch to 6.5mm just for a slight improvement in trajectory and wind drift? ...

This is a false assertion unless one refers to existing bullets.

Physics tells us that, for the same bullet weight, the 6.5 enjoys a greater sectional density. That alone will give it an edge.

The fact that the 6.5 carries velocity better means that it will also retain its armor defeat ability further out.

[Double Naught Spy]

So a 6mm bullet would be better than 6.5 would be better than 6.8?

[BluntForceTrauma]

Those numbers look suspiciously like they were chosen to rule out bullets bigger than 6.5mm.

No. But, yes, practically speaking.

A cartridge diameter of 0.473" would result in magazines as wide and tall as for 7.62 NATO, making 30-round magazines too bulky to be practical.

Wow, that mag is a BEAST. A fair point — 0.473" is too bulky. Back to 0.440.

[BluntForceTrauma]

So a 6mm bullet would be better than 6.5 would be better than 6.8?

So it would seem — if armor penetration at distance drives the requirement and if one also wants to keep overall bulk down.

Here's a thought experiment: What would it take to drive a 6mm 110gr-bullet to a muzzle velocity of 3,000 fps?

110gr cuz let's assume tungsten or something dense wants to be used, in the worst case, for armor penetration.

Using an 80,000 psi chamber pressure, what is the overall length of the case and the diameter of the case head?

Using today's standard technology, the 6mm GT meets the above requirement with a 0.473 case head and 1.7" case length.

If the chamber pressure is increased like they're doing for NGSW, how much can the case shrink?

[LRRPF52]

Case polymer wall thickness on CT is driving magazine bulk and linked ammunition volume as well.

Polymer needs to be a certain thickness in order to prevent case failure at the pressures they’re pushing.

An equivalent or even lighter 6.5mm with better BC would meet the armor defeat requirement.

[stanc]

Case polymer wall thickness on CT is driving magazine bulk and linked ammunition volume as well.

There are three factors which determine CT cartridge diameter: Wall thickness; propellant space between the case wall and bullet; and bullet diameter.

Of those factors, the case wall thickness actually contributes the least to the cartridge diameter. The primary factor driving cartridge bulk is bullet size.

The bullet diameter determines the cartridge diameter, and the bullet length determines the cartridge length. Together they determine the magazine bulk.

An equivalent or even lighter 6.5mm with better BC would meet the armor defeat requirement.

Unfortunately, even if that's true, switching to 6.5mm would allow so little reduction in cartridge size, there would be no change in magazine bulk or capacity.

[LRRPF52]

That CT case wall thickness is much thinner than I thought.

A larger diameter projectile with a high BC takes up more propellant volume, which requires a larger case.

What’s the difference in size between the 5.56 LSAT CT and the 6.8 NGSW CT?

When they did the 6.5 LSAT, it looked like the cases were about the same size as the 7.62 CT cases.

If they used the 5.56 LSAT exterior profile with a .257” VLD/EPR, that would be more ideal.

We know as soon as this whole thing is nailed down, the Russians and Chinese will likely have the next generation body armor developed, not that US Infantrymen are going to meet them on the field of battle on equal terms anyway.

I would love a little .257” LMG that fit the profile and handling of the 5.56 LSAT. If they wanted to up the chamber pressure without reducing long-term serviceability/durability, that’s fine.

[grayfox]

Back to the pressure vs MV question by BFT.
One excel spreadsheet formula and theory developed (airc) that exit MV is related more to the 1/4 max P vice the actual max P...
If that is true, then going from say 2500 ft/s (20" barrel) in a 6.5 Grendel at 52,000 psi, to an 80,000 would be:

2500 ft/s*0.25(80K)/[0.25(52K)] = 3846 ft/s. (not 4167 as I wrote earlier, math boo-boo).

Not too shabby.

[stanc]

What’s the difference in size between the 5.56 LSAT CT and the 6.8 NGSW CT?

I have not yet seen published dimensions for the 6.8 NGSW CT round, but -- as best I can measure it (in the middle photo of post #80) -- the 6.8 CT is ~2.6" long, with ~0.5" diameter.

I would expect the 6.8 CT to have the same 0.504" diameter as the 7.62 CT cartridge. However, I have no means to measure the image with any precision, so it could be a hair smaller.

When they did the 6.5 LSAT, it looked like the cases were about the same size as the 7.62 CT cases.

The 6.5 CT case is exactly the same size as the 7.62 CT case. The 6.5 CT uses the 7.62 case, but with a different nose plug to fit the smaller caliber projectile.

If they used the 5.56 LSAT exterior profile with a .257” VLD/EPR, that would be more ideal.

The 5.56 CT case is dimensioned to take a .224" bullet. You can't stuff a .257" bullet into it. A fatter, longer bullet will require a fatter, longer case.

We know as soon as this whole thing is nailed down, the Russians and Chinese will likely have the next generation body armor developed, not that US Infantrymen are going to meet them on the field of battle on equal terms anyway.

Yeah, well, I don't see infantry combat against Russian or Chinese troops as very likely. The US has always avoided going to war against nuclear powers.

I would love a little .257” LMG that fit the profile and handling of the 5.56 LSAT. If they wanted to up the chamber pressure without reducing long-term serviceability/durability, that’s fine.

I won't be surprised if NGSW suffers the same fate as the ICSR, OICW, and other programs that preceded it. Perhaps they'll rethink the matter after testing and evaluation are completed, and decide to downsize the caliber.

[LRRPF52]

I’m thinking back to this slide from LSAT:

[stanc]

I’m thinking back to this slide from LSAT...

What about it?

[LRRPF52]

Impact energy.

[LRRPF52]

Maybe I’ve overlooked the possibility of having to defeat foreign armies clad in armor on our own soil.

[stanc]

That seems like a zero-probability event.

[LRRPF52]

That seems like a zero-probability event.

China’s Role in UN Peacekeeping - Growing Contribution

Summary
* From the 1980s China has a more active foreign policy agenda and by the 1990s is contributing personnel to UN Peacekeeping missions.
* China is now the second largest contributor to the UN Peacekeeping budget.
* Peacekeeping contributions have steadily become an important part of China’s soft power strategy.
* China’s involvement forms part of a broader foreign and economic policy that is primarily centered on force projection and commercial interests.
* China’s peacekeeping initiatives have fostered cooperation and represent an opportunity to improve bilateral and multilateral relations.

Council on Hemispheric Affairs Article entitled “Filling the Void: China’s Expanding Caribbean Presence"

The Peace Ark sailed smoothly into Havana Harbor, floating past the aging brick Morro Cabana fortress under a luminous yellow sun. The Ark’s 416 crew members disembarked on a warm Friday afternoon in October 2011 without much pomp, pageantry, or even a token media presence.[1] The white ship featured little ornamentation aside from a red hospital cross that was painted to denote its ostensible purpose: “offering medical service to local people.”[2] Yet, despite this humble presentation, the crew’s “Harmonious Mission” had profound geopolitical significance. This voyage represented the first naval exercise in the Caribbean by the Chinese Navy.

In the years following the arrival of the Peace Ark, China has continued to expand its engagement with the Caribbean on economic, political, and even military fronts.[3] Economically, China has begun to pour substantial funds into infrastructure investments, deals which often impose heavy burdens on their Caribbean recipients. On the political side, China has increasingly paid diplomatic attention to Caribbean nations, including Washington’s regional foe, Cuba. This presence also features arms sales and security cooperation. China’s growing regional role could pose a substantive strategic threat to American security or to its economic goals. Washington should not continue to ignore this growing trend. China’s increased economic and political ties to the Caribbean represent a symbolic challenge that the U.S. should prepare to respond to with increased diplomatic and cultural outreach.

Reuters: Chinese Paper says US should learn from China, restrict guns, protect rights

"Gun ownership in China is strictly regulated, which helps reduce gun-related crimes and deaths. The U.S. should learn from China and genuinely protect human rights,” it said.

Human rights have long been a source of tension between the world’s two largest economies, especially since 1989, when the United States imposed sanctions on China after a bloody crackdown on pro-democracy demonstrators around Beijing’s Tiananmen Square.

China rejects criticism of its rights record, pointing to its success at helping millions escape poverty, and regularly attempts to deflect the issue by calling attention to its critics’ own problems.

I’ll take 12 NGSWs and a few cases of ammo please.

[stanc]

China’s Role in UN Peacekeeping - Growing Contribution

Council on Hemispheric Affairs Article entitled “Filling the Void: China’s Expanding Caribbean Presence"

Reuters: Chinese Paper says US should learn from China, restrict guns, protect rights

Interesting developments, but an invasion by a foreign army still seems like a zero-probability event.

It's one thing to sail a single, unarmed hospital ship into a Cuban port. Amassing an invasion fleet and conducting D-Day landings on US beaches is quite another.

I’ll take 12 NGSWs and a few cases of ammo please.

I wouldn't mind having an NGSW-AR and a few cases of ammo, just for fun.

In the event of a Chicom invasion, I'll take a dozen Javelin missiles, please.

[LRRPF52]

Is it still considered an invasion if they are invited in to help “keep the peace” in a post-civil war landscape?

[stanc]

Is it still considered an invasion if they are invited in to help “keep the peace” in a post-civil war landscape?

If an international peacekeeping force were here at the request of the US government, it would be illogical to consider it an invasion.

Although if the Army, Marines, and National Guard were to be so damaged/depleted by the hypothetical civil war that they could not restore and maintain order, I think it's very questionable that there would be a functioning federal government to "invite" foreign peacekeepers.

So, this also seems like a zero-probability event.

[grayfox]

Could be sent here at request of a "Notmypresident" like HidinBidin... I would call that an invasion.
And he'd (or his boy) probably make a few biIIion$ from it.
Same-o, same-o.

Ok, rant over. Couldn't help myself...

[stanc]

Could be sent here at request of a "Notmypresident" like HidinBidin... I would call that an invasion.

I don't know who "HidinBidin" is, but I am sure that some Americans would view international peacekeepers as invaders, even if they were genuinely needed to restore and maintain order in the aftermath of a hypothetical Civil War III.