Russian War Machine vs. Princes of Islam
#1
No, this is not a new treatment of the Soviet experience in Afghanistan, but is a comparison of the closest thing we have to mass-produced military loadings in both 6.5 Grendel and 6.8 SPC, with 5.56 M855 thrown in for good measure.

The Russian state arsenal in Barnaul, the same arsenal producing Russian military 7.62x39 and 5.45x39 by the hundreds of millions, is producing steel-cased 6.5 Grendel with a 100gr FMJ for the U.S. commercial market. One of the largest U.S. military ammunition manufacturers, ATK (via Federal), is producing 6.8 SPC with a 90gr Gold Dot (or Fusion) bullet for contracts with the Saudi Arabian and Jordanian palace guards, tasked with protecting their respective royal families.

The 6.8 SPC loading is specifically a military loading for a military contract. This loading was tested by no less a personage than wound ballistician Dr. Gary Roberts. He reports that in a 16" barrel the muzzle velocity is 2604 fps. When 6.8 fans challenged his findings, claiming that his velocity readings should be much higher, he retorted, "That is the velocity out of a 16" barrel at 3 meters — given that this loading is specifically built for a military contract, I suspect ATK want to ensure moderate pressures to enhance weapon durability and service life. Screaming velocity and high pressures have NO place in service weapons — especially those used in high temperature environments like this new 6.8mm loading is destined for."

Likewise, Wolf steel-case ammunition is known for its very mild velocities, and their 6.5 Grendel loading is no exception. Gun writer David Fortier reports the 100gr FMJ runs 2496 fps from a 16" barrel. Designer of the 6.5 Grendel, Bill Alexander, has also controlled the pressure specification of factory ammunition, to address precisely the concerns cited by Dr. Roberts.

Often there are complaints from one side or the other that one is not making an apples-to-apples comparison, but this is the closest yet we have to military loading vs. military loading. When the technical minds at ATK load a different 6.8 bullet or when the technical minds at the Russian arsenal create additional 6.5 loadings, we'll revisit the data.

I've created four charts comparing velocity, trajectory drop, wind drift, and energy for 16" barrels in the 6.5 Grendel, 6.8 SPC, and 5.56 NATO M855. I've also included my source tables, generated from the JBM ballistics calculator.
:: 6.5 GRENDEL Deer and Targets :: 6mmARC Targets and Varmints and Deer :: 22 ARC Varmints and Targets

:: I Drank the Water :: Revelation 21:6 ::
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#2
Looks like a no brainer to me.... Can you get a chart added with recoil statistics as well?
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#3
I learn something new every time I log on here. Great info, thanks for posting.
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#4
Great info!!! Any chance of adding the LC M80 to the charts?
"Those who sacrifice liberty for security, deserve neither." Benjamin Franklin
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#5
Nicely done, John. But isn't posting it here rather like "preaching to the choir"?

Maybe it ought to go on arfcom? Smile
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#6
Job well done. Unfortunately I used up a brain cell. Just kidding.
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#7
Thanks John. Good stuff.Smile
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We either hang together on this, or we'll certainly HANG separately.....
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#8
HANKA Wrote:One of the largest U.S. military ammunition manufacturers, ATK (via Federal), is producing 6.8 SPC with a 90gr Gold Dot (or Fusion) bullet for contracts with the Saudi Arabian and Jordanian palace guards, tasked with protecting their respective royal families.

The 6.8 SPC loading is specifically a military loading for a military contract. This loading was tested by no less a personage than wound ballistician Dr. Gary Roberts. He reports that in a 16" barrel the muzzle velocity is 2604 fps. When 6.8 fans challenged his findings, claiming that his velocity readings should be much higher...
After watching the video below, I'm not surprised they questioned that 2604 fps reading.

https://www.youtube.com/watch?v=uoX68gSOfsA

Note the 16" chrono'd MV of 2850 fps, seen at 6:21-6:32 in the video.

I wonder why such a huge difference?
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#9
They're shooting it so close to the chronograph that the muzzle blast is shaking the thing. It's an optical device, shaking it will very clearly throw off any data. That's what we call useless data.
"Those who sacrifice liberty for security, deserve neither." Benjamin Franklin
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#10
In regard to a "Russian War Machine," I would happily surrender to this one:

[Image: hubba-hubba-smiley-emoticon.gif] [video=youtube;IFKYPDHv2zU]https://www.youtube.com/watch?v=IFKYPDHv2zU[/video]
https://www.youtube.com/watch?v=IFKYPDHv2zU
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#11
cory Wrote:They're shooting it so close to the chronograph that the muzzle blast is shaking the thing. It's an optical device, shaking it will very clearly throw off any data. That's what we call useless data.

You mean the manufacturers have some kind of reason for telling you to place the chronograph 15 feet away? They just didn't pull 15 feet out of their hat?

You can see the chrono getting hit hard with the muzzle blast in the video. I would like to say I'm surprised that they did that, then made it public. Not much surprises me anymore though.
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