Military round comparisons

[Tony Williams]

I saw, not long ago, the results of an analysis done of various rifle calibres. I can't provide more details of the circumstances, other than to say it was in a military context. The study (a paper exercise using various ballistic and other performance software available to the military) compared the performance of the 6.5 Grendel (123 grain OTM), 6.8 Rem (115 grain OTM), 7.62mm M80, 5.56mm M855 and 5.56mm MK262. It wasn't intended to be a particularly exhaustive analysis, but I thought you might like the outcome:

In external ballistics, the rounds fell into three groups: the M855 and 6.8mm Rem were very similar; the M80 and MK262 were also very similar, and much better than the first pair; the Grendel was by itself, waaaay out in front on every metric (including calculated barrier penetration). The work included the effects of wind drift as shown on some typical "advancing man" targets at 300m. I didn't note the wind speed, but a shot aimed centre-mass would have hit very close to centre mass with the Grendel, and just clipped the edge of the target with M855.

None of this will come as any surprise to anyone on this forum, of course, but it was nice to see this coming from a military source.

I did point out that replicating these performances with copper+steel bullets as currently favoured by the US Army would be difficult (probably impossible with MK262), due to the considerable extra length required.

[LRRPF52]

It is interesting to see that the UK and other armies are looking for the compactness and performance that the Grendel provides in an interim system between a battle rifle and an assault rifle, largely driven by the combination of losing the terminal effects of 7.62 NATO at distance after ditching the FAL/G3, with renewed demand due to the geography in Afghanistan.

I suspect that a certain country in the Eurasian region is going to adopt the Grendel, and then it will be a catch-up game after that. I was disappointed to hear from the Czechs that they were seriously looking at the 6.8 for the Bren 805, but it is a quick barrel change system, so it is easy to change if they see the light, and they can make magazines specific to the Grendel when the time comes.

Again, when someone finally makes a Grendel LMG, that will get the ball rolling, but the logistics inventory currently supports 11 years of 5.56 NATO and 7.62 NATO, and it becomes an issue of letting "great" becoming the enemy of "good enough" to the big picture planners.

In the economic discussion, the argument could be made that a universal caliber system will have long-term cost-savings for a nation not in the NATO system, or looking to carve out their own logistics and weapons programs as NATO continues to ignore their national interests in the face of a resurging Russia, who is a very likely candidate to adopt the Grendel themselves, especially when you look at the benefits it would offer them over the 7.62x54R belt-fed and DMR weapons (SVD).

[LR1955]

I saw, not long ago, the results of an analysis done of various rifle calibres. I can't provide more details of the circumstances, other than to say it was in a military context. The study (a paper exercise using various ballistic and other performance software available to the military) compared the performance of the 6.5 Grendel (123 grain OTM), 6.8 Rem (115 grain OTM), 7.62mm M80, 5.56mm M855 and 5.56mm MK262. It wasn't intended to be a particularly exhaustive analysis, but I thought you might like the outcome:

In external ballistics, the rounds fell into three groups: the M855 and 6.8mm Rem were very similar; the M80 and MK262 were also very similar, and much better than the first pair; the Grendel was by itself, waaaay out in front on every metric (including calculated barrier penetration). The work included the effects of wind drift as shown on some typical "advancing man" targets at 300m. I didn't note the wind speed, but a shot aimed centre-mass would have hit very close to centre mass with the Grendel, and just clipped the edge of the target with M855.

None of this will come as any surprise to anyone on this forum, of course, but it was nice to see this coming from a military source.

I did point out that replicating these performances with copper+steel bullets as currently favoured by the US Army would be difficult (probably impossible with MK262), due to the considerable extra length required.

Tony:

Seen it before. Compare $2.00 a shot match grade 6.5 Grendel with $.50 a shot ball ammo. Run everything on a computer, manipulate data, and low and behold, the $2.00 a shot Lapua match Grendel ammo outshoots everything else and is more lethal.

No military in the world has the money to use match grade Lapua ammunition for ball ammunition. Now, once again, lets look at a 120 grain ball bullet using a charge that will not blow an AR-15 into pieces and I imagine the outcome would probably be much different.

And, who is making Grendel magazines that are reliable?

LR1955

[stanc]

No military in the world has the money to use match grade Lapua ammunition for ball ammunition. Now, once again, lets look at a 120 grain ball bullet using a charge that will not blow an AR-15 into pieces and I imagine the outcome would probably be much different.

Indeed. Comparisons of 6.5 Grendel w/match bullet vs 7.62 M80 Ball prove nothing. The Norma 120gr FMJ is what should've been used, and with it, wind drift is no better than with M80, while trajectory is slightly worse.

And, who is making Grendel magazines that are reliable?

I think that issue could be resolved, although to do so it may be necessary to follow the LWRC lead (with the 6.8 weapons made for Saudi Arabia) in making a caliber-specific lower receiver and wider magazines.

Far more critical is whether or not viable disintegrating links can be developed. Unless that can be done, it doesn't matter how good 6.5 Grendel performs as a rifle cartridge.

[ricsmall]

After watching Azprcs' vids, Im wondering how feasible it would be to put the Grendel in the hands of a scout/sniper team or even DMR role to start with. Takes the DMR to new levels over 5.56 and lightens the load of a sniper. Ammo is no longer interchangeable with everyone on the battlefield, but, not everyone on the battlefield carries 118LR or 118 Special ball. Just wondering, as I may be way off base,so you guys be easy on me! Of course with a scout/sniper team, the 6.5G might be a mission specific tool as opposed to say a .300 WM or a .338LM.


As stan said, it may require following LWRC and changing the lower up. I definitely think it would be a worthwhile replacement for the M110 or whatever the designation of the stoner 7.62 is this week.

As far as magazines, we have the technology to shoot a specific spot with an ICBM thousands of miles away, yet we cant figure out a reliable grendel mag design?:confused:

[BluntForceTrauma]

Russia, who is a very likely candidate to adopt the Grendel themselves, especially when you look at the benefits it would offer them over the 7.62x54R belt-fed and DMR weapons (SVD).

I worry about the damn Russians. Well, not worry, but wonder. Their military-industrial complex IS doing some serious development work on the commercial steel-case 65G. Not a huge stretch to imagine the beauty of its ballistics in an AK-sized weapon are not lost on them, relative to both 7.62x39 and 5.45x39, as well as 7.62x52. Add to that their Federov, all those years ago, was chambered in 6.5!

And they don't give a rip whether a cartridge has the backing of big American sporting goods manufacturers or the marketing aura of "special operations" development and "imminent adoption" by the U.S. Army and the FBI and the CIA and, well, you get the drift. . . . They're gonna look at raw performance, not flashy marketing.

John

P.S. And, Stan, I guess the infidel 6.5 Grendel will NOT have the distinction, as it's older brother does, of having been a cartridge rejected by the US Army and USMC and adopted by the land of jihadis and 911 perpetrators.

[bwaites]

Tony:

Seen it before. Compare $2.00 a shot match grade 6.5 Grendel with $.50 a shot ball ammo. Run everything on a computer, manipulate data, and low and behold, the $2.00 a shot Lapua match Grendel ammo outshoots everything else and is more lethal.

No military in the world has the money to use match grade Lapua ammunition for ball ammunition. Now, once again, lets look at a 120 grain ball bullet using a charge that will not blow an AR-15 into pieces and I imagine the outcome would probably be much different.

And, who is making Grendel magazines that are reliable?

LR1955

LR1955, aren't the Army and Marines already buying match grade 5.56 ammo from Black Hills and giving it to a fairly large group of soldiers/Marines? And everyone that has the chance to is ordering it or sucking it out of the supply chain if they get a chance. From the guys I've talked to, they all saw Mk 262 ammo in the sandbox or 'stan and grabbed it. They shot whatever they could get, but some of the time they could get Mk 262. Granted, it isn't Lapua Scenars, but the 123 SMK is close enough and I have to believe that any of the larger armories could easily tool up and make a very comparable bullet, couldn't they?

The magazine issue could be fixed relatively easily if there was enough concern. BTW, new production ASC seems to have eradicated most of the issues with mags.

In addition, from what Alexander posted on ARF.com, there will be a new player in a very short time.

[tcte]

In addition, from what Alexander posted on ARF.com, there will be a new player in a very short time.

What are you refering to? i havnt seen a post from Alexander on arfcom in a long time, last good rumor i heard was that Colt was stepping up to the plate

[stanc]

I worry about the damn Russians. Well, not worry, but wonder. Their military-industrial complex IS doing some serious development work on the commercial steel-case 65G. Not a huge stretch to imagine the beauty of its ballistics in an AK-sized weapon are not lost on them...

I agree. I was only half joking when I said that maybe they're doing concurrent development of 6.5 Grendelski for the Russian military.

P.S. And, Stan, I guess the infidel 6.5 Grendel will NOT have the distinction, as it's older brother does, of having been a cartridge rejected by the US Army and USMC and adopted by the land of jihadis and 911 perpetrators.

Ha! Y'know, at some point down the road, that could possibly bring a whole new dimension to the 6.8 vs 6.5 debate. Imagine the two calibers being on opposite sides of a future battlefield... :eek:

[bwaites]

What are you refering to? i havnt seen a post from Alexander on arfcom in a long time, last good rumor i heard was that Colt was stepping up to the plate

Mags, almost at the bottom of the first page in this thread.
http://www.ar15.com/forums/t_3_121/58035...tml&page=1

[stanc]

LR1955, aren't the Army and Marines already buying match grade 5.56 ammo from Black Hills and giving it to a fairly large group of soldiers/Marines?

Yes, but it isn't $2.00 per round Lapua match ammo.

Plus, match hollowpoint bullets aren't fired in machine guns.

What is needed to properly evaluate and demonstrate the military capability of 6.5 Grendel is a good, general purpose, ball bullet. Comparing ballistics of a Lapua Scenar to M80 Ball is misleading, at best.

[bwaites]

It's not a Lapua match round, it's a Lapua bullet. That said, the Sierra is comparable, and is available loaded from he same company!

If the military decided they wanted it, they could manufacture a ball round with the same ogive and ballistics, no problem.

[stanc]

If the military decided they wanted it, they could manufacture a ball round with the same ogive and ballistics, no problem.

My understanding is that going from HPBT to FMJBT reduces BC, and adding a cannelure to the bullet jacket also reduces BC. If that's so, then it seems to me that a ball projectile of the same shape and weight would necessarily have worse ballistics.

[stanc]

...I guess the infidel 6.5 Grendel will NOT have the distinction, as it's older brother does, of having been a cartridge rejected by the US Army and USMC and adopted by the land of jihadis and 911 perpetrators.

I suppose not. But, I gotta say, that UCIW is a pretty cool looking little package.



Somebody refresh my memory, please. Is 6.5 Grendel usable with an 8.5-inch barrel AR? Are the internal ballistics -- pressure curve, gas volume, or whatever -- compatible, or is 10.5 inches the shortest length that will work?

[Tony Williams]

My understanding is that going from HPBT to FMJBT reduces BC, and adding a cannelure to the bullet jacket also reduces BC. If that's so, then it seems to me that a ball projectile of the same shape and weight would necessarily have worse ballistics.

The BC is determined by two factors: the sectional density (how heavy it is for the calibre) and the shape (form factor or FF), especially of the ogive. If the calibre and weight remain constant, then the FF determines the BC. As far as I'm aware there is no fundamental reason why an HPBT should have a better FF than FMJBT. I have always understood that the reason for wrapping the jacket around the base is that this has been found to improve the consistency of performance and therefore accuracy.

A cannelure is a separate issue as that could indeed affect the FF. I don't know to what extent, nor how important the different types or locations of cannelure might be - nor indeed how necessary it might be to have one, rather than securing the bullet in the case in some other way. If one is necessary, then I suspect that placing it well back along the bullet body would have less effect than closer to the nose.

Edit to add: a bore-rider type bullet needs no cannelure anyway, as the case mouth could crimp into one of the grooves.

[Schwag173]

Based upon the recent adoption of the M855A1 (5.56mm) round as standard issue, I doubt there will be any DoD interest in the Grendel. http://www.army.mil/article/48657/

[LRRPF52]

The PEO has a tendency to embellish and doctor their conclusions before reaching them. We discussed this in-depth on the old forum, and a cursory analysis of the accuracy results of the M855A1, for example, show some pretty skewed thinking on the way they manipulated the data.

If they are trying to say that M855A1 will replace 7.62 NATO, we know they're smoking crack again. They tried that idea back in the 1980's, saying the SAW can replace the M60. This is what happens when non-experienced desk jockeys are allowed to make decisions way outside of their compentency. If you have some dude in charge of PEO who doesn't know his rectal muzzle from a foxhole, you get some really hysterical, yet scary ideas floating around.

If the M855A1 proves superior to M855, then by all means, use it for 5.56. The real question is what are we going to do with LMG's?

[Trooper]

I became interested with the article in Shooting Times. Everyone knows that the military is finding the 5.56x45 to just be too light. Also that we are now carrying two different cartridges (.223 and .308) which means to seperate platforms, two mags and two MGs. Thus you have a M4, a SAW, IAR, DMR (.308) and the med MG (.308). And that is just per squad.

I like the 6.5mm Grendel. Just concerned that it would be the best as a general purpose cartridge (GPC). Would we be better off with a 7mm or a longer case? Should we just scrap the M16/M4 platform? The Grendel does a great job working within the current platform. But would it be the best cartridge for the GPC?

I am seeing a lot of interest in the 6.5mm. Arthur Brown (http://www.eabco.com) is really pushing it for the Thompson Encore platform (6.5mm BRM is based on the .30-30 and has a performance is near the 6.5x55mm Mauser). I am putting together a piece on the GPC that I have gleaned from other sources.

[LRRPF52]

My problem with General Purpose Cartridges is that they aren't well-suited for important engagement scenarios, and soldier's load considerations, particularly when you understand the relationship between soldier's load and combat endurance.

If there is one candidate for a GPC, the Grendel is the cartridge to beat, but you would still need 2 or 3 different loads for it ideally:

An assault rifle load with a lighter projectile of 100gr or less, with high velocity

A Light Machine Gun Load pushing a high BC FMJBT of 130gr at 2600fps or more

A DM/Sniper load of a 123gr BTHP pushed at 2600fps

That kinda makes the assault rifle load questionable in comparison to the 5.56, since 5.56 is an awesome little cartridge that I can carry a ton of, resulting in the extended fighting duration of my unit.

7.62 NATO should be the cartridge that is phased out, and replaced with a 6.5mm LMG and DM/SASS cartridge.

[Schwag173]

If there is one candidate for a GPC, the Grendel is the cartridge to beat, but you would still need 2 or 3 different loads for it ideally:

That kinda makes the assault rifle load questionable in comparison to the 5.56, since 5.56 is an awesome little cartridge that I can carry a ton of, resulting in the extended fighting duration of my unit.

7.62 NATO should be the cartridge that is phased out, and replaced with a 6.5mm LMG and DM/SASS cartridge.

I agree with everything you just said, LRRPF52, but I think events are going to dictate otherwise. The Pentagon crowd is looking at massive downsizing and will see this as a time to 'make-do' with what we've already got. Helluva shame, though. I'd love to see 6.5 Grendel replace 7.62x51.