Grendel as a Universal Infantry Cartridge

[Tony Williams]

My take on the performance requirements is this:

1. Both US and UK armies officially see the 5.56mm as having adequate performance up to 400m.

2. Both US and UK armies see the 7.62mm M80 as providing adequate performance for the 400-800m range bracket (in rifles) and 1,000+m in GPMGs.

Therefore, to justify its existence any new round merely has to provide comparable hit probability and target effects to 7.62mm M80 over the 400-1,000m range bracket (while saving as much weight as possible), with superior barrier penetration and terminal effects than 5.56mm over 0-400m being a nice bonus.

The key concern of both armies where dismounted infantry is concerned is weight - so it's the lighter replacement for 7.62mm which is the main selling point, with the various other advantages of a single-calibre solution adding to the argument.

[stanc]

The most recent breath of fresh air is the observation by LRRPF52 that some East European countries might develop an interest in the cartridge. Let's help him pursue that notion and see where it takes us.

http://www.65grendel.com/forum/showthread.php?984-Grendel-LMG

Others have told us that the link problem will almost certainly be solved once the resources are made available.

In the absence of evidence which supports that claim, I'm going to have to remain skeptical. However, I'll drop the question of disintegrating link design if we're going to concentrate on the notion of possible Eastern European use of 6.5 Grendel, since AFAIK (and I hope LRRPF52 will confirm) they utilize non-disintegrating links.

Continuing to harp on that and the testing topics suggests that your audience has the wherewithal to demonstrate new link designs and to do the kinds of testing the government either conducts in-house or funds contractors to do.

WARNING: Stuck Record Ahead. As I've said many times, in order to demonstrate relative performance of 6.5 Grendel and 7.62x51 (or in the case of E. Europe, 7.62x54R), we do NOT have to do testing to the same standards as the government employs.

Less formal testing can prove that 6.5 G is as capable as proponents have long asserted, or show that the reality doesn't live up to the theory.

We, even as a collective body, would be hard-pressed to define and execute unsolicited testing that would be viewed as credible, even if we could somehow get the funds from non-government sources.

Oh, baloney. Even if you wish to think we are too simpleminded to devise credible tests, FBI and military tests can be followed.

Further, I recall an admonition from Bill Alexander that some of the testing advocated can easily be counterproductive. I have indicated in prior posts that my own experience validates Bill's concerns.

Argh! That's an excuse to sit on our hands and do nothing, except more talk, talk, talk. Blah, blah, blah. We've been discussing these questions since 2005. If we follow what you and Bill want, we'll still be discussing them in 2025. It's time to stop talking and start testing.

[Variable]

Sorry in advance for OT, but Jaywalker just rang my bell.LOL

Speaking as a penetrator (in my B-52 role), I was delighted to have Short Range Attack Missiles and Air-Launched Cruise Missiles, both for mission capability and for cluttering up radar returns.

Arggh!!! Flashbacks!!!LOL. I didn't know there were SAC folk here. A BUFF driver? Ever come through Andersen? My first tour was 43rd Bombardment. SRAMs and big 'ole silver suppositories! LOL. I left SAC to TAC, but SAC taught me how to live for the rest of my life!!!

Peace is Our Profession...
Mwuuhahahahahaa!

[Variable]

SAC was my first PCS after learning B-52 repair at Shitnute.

I recall I was thrilled (if a bit puzzled) to be assigned to P-47s.

Then I got to Lincoln and discovered it was actually B-47s...

You sound like me heading to Guam with a PACAF flash on my beret and then finding out only after I got there that I was actually in SAC. Talk about a shocker! Everyone at Lackland had been telling me how laid back PACAF was, and how easy I'd have it there. I stepped into the gauntlet without even having a clue!

B-47? Bwaaahahahaha! At least the "BUFF"s are still flying. Now I feel young again! Thanks!LOL

[Jaywalker]

I dropped BUFFs just as quickly as I could, figuring I'd rather guard a missile hole in North Dakota than set butt in another BUFF. I switched to the Air National guard and learned the reconnaissance F-4 world, the RF-4C as a WSO. At least B-47 flights were shorter so the pain was less...until you got to those planned one-way flights, I guess. Though, there were times I hoped the BUFF engines would flame out or even burn so we could land.

By the way, they did on occasion, and the single seat pilots got quite a charge when we declare an In-Flight Emergency with an inop engine - they called it the "Dreaded Seven Engine Approach!"

[Variable]

I dropped BUFFs just as quickly as I could, figuring I'd rather guard a missile hole in North Dakota than set butt in another BUFF. I switched to the Air National guard and learned the reconnaissance F-4 world, the RF-4C as a WSO. At least B-47 flights were shorter so the pain was less...until you got to those planned one-way flights, I guess. Though, there were times I hoped the BUFF engines would flame out or even burn so we could land.

By the way, they did on occasion, and the single seat pilots got quite a charge when we declare an In-Flight Emergency with an inop engine - they called it the "Dreaded Seven Engine Approach!"

Heh heh, I love the old BUFFs. I'll never forget the first elephant walk I saw. I rotated between alert sentry and the WSA, and they had an elephant walk while I was outside on a SRT patrol by the WSA. We watched the Alert BUFFs quick start, role out of the alert area to the hammerhead, and then TAKE OFF!!!!!.................. What we didn't know was that there were other non-alert BUFFs behind a slight rise we couldn't see at that end. THOSE were the ones that took off. The whole WSA and about half the base went apesh!# on that one. It was a real cool trick they played on everybody, and really made you think. We always wanted to be sentry on "the day", hoping you guys would take us along to have a rifle on board if you ever really went. At 18 I never thought to wonder how we'd get back down, but we figured it would have been a heck of a ride if they ever actually had.

I did get to ride on the CINCLANT bird at Langley. That was cool. Not near as exciting as a one way trip on a BUFF would have been though.

[JASmith]

...Not near as exciting as a one way trip on a BUFF would have been though.

After seeing all the SAR going on in Vietnam, I kind of wondered why the AF survival manuals stressed so many long term survival practices. Same for the survival rifles that went with the kits.

Took years for for me to finally realize that the world the crews were being prepared for was one where there would be few cities and staying alive would likely be a subsistence game lasting a lifetime...

[Variable]

Yep, atom tans for everybody!

[stanc]

Possible bullet design for 6.5 Grendel assault rifles?

Below: 7.62x39 123gr / .300 Blackout 125gr

[JASmith]

Stan,

Are you thinking of a linear scale (length and diameter) or just reducing the diameter?

The linear scale would give a bullet right at 80 grains, while reducing the diameter would be about 92 grains.

This could be a path to getting 3000 ft/sec. The long nose may make up for the lack of boat tail for ranges typical of infantry engagements.

The design looks like it could readily tumble when hitting something.

[stanc]

Stan, Are you thinking of a linear scale (length and diameter) or just reducing the diameter?

Joe, I actually hadn't given it any thought. But, since you ask, I'm guessing it'd have to be a linear scale in order for cartridge OAL to fit in the magazine.

The linear scale would give a bullet right at 80 grains, while reducing the diameter would be about 92 grains.

This could be a path to getting 3000 ft/sec. The long nose may make up for the lack of boat tail for ranges typical of infantry engagements.

That's kinda what I had in mind, too.

The design looks like it could readily tumble when hitting something.

Concur. I dunno if the PDF below has a gel test for this bullet. Since the file size is 8MB, I didn't try opening it.

http://300aacblackout.com/resources/300AACBlackout06OCT2010.pdf

[JASmith]

,,,I dunno if the PDF below has a gel test for this bullet. Since the file size is 8MB, I didn't try opening it.

http://300aacblackout.com/resources/...t06OCT2010.pdf

I looked over the PDF -- lots of gel tests on:

Hornady 110gr V-Max
Speer 125gr TNT
Nosler 125gr Ballistic Tip
Remington 125gr Accutip
Sierra 125gr Pro Hunter JSP
Hornady 130gr SP
Barnes 110gr TSX

But, there appeared to be no FMJ bullets in the tests.

[stanc]

I looked over the PDF...there appeared to be no FMJ bullets in the tests.

Uhhh...did I neglect to mention it's not FMJ?

It's a Sierra MatchKing. With secant ogive!

Midway has 'em (except reportedly without the cannelure).

http://www.midwayusa.com/Product/915404/sierra-matchking-bullets-300-aac-blackout-308-diameter-125-grain-open-tip-match-otm-box-of-500

[JASmith]

Thanks for the link. The operative ballistic coefficient is 0.338 G1.

Gel block tests for this one should be interesting.

[LRRPF52]

I don't see what would be wrong with putting a short boat tail on this, like the M193 55gr. Either way, that would be a great assault rifle load, especially if it was screaming at 2900fps. The longer we can extend the 2600fps lead shower threshold, the better. This would mean a thin jacket, and the cannelure helps with jacket separation in conventional projectiles. Put a penetrator buried in the core of the bullet, with a concealed hollow-point, and now we're talking multi-purpose.