FMJ yaw and upset performance

[LR1955]

I have read similar complaints about barrier (in general) and windscreen (in particular) penetration from a study of combat experience carried out by the Royal Marines last year (which included the SBS - their SEALS). This study showed that only about half of the Marines consulted felt that the 5.56mm ammo was "fit for purpose"; there was a majority view that an intermediate round could solve these problems; and that if that wasn't possible, they tended towards entirely replacing 5.56mm with 7.62mm.

Tony:

And I would say well over 90% of this is anecdotal and pure opinion. Lets see the empirical studies.

A Soldier will always opt for what looks cool but when you run them through the simplest of evaluations you find that the chances of them actually hitting anything is small and gets smaller as the recoil and blast increases.

You will find that in most cases a Soldier will get the notion a cartridge sucks because he isn't hitting anything and blames the cartridge when he probably never even zeroed his carbine (happens more often than you may think) and otherwise is a lousy shot. Another one is that Soldiers will tend to believe that just because a cartridge is bigger such as 7.62 vs 5.56, that it must be better.

In the case of intermediate penetration and terminal effects, I tend towards scientifically run experiments more than a Joe's opinion. I have seen way too much over the years to trust the opinions of most (not all) military folks when it comes to small arms capabilities. There are some I do trust -- but most I don't.

Bottom line is that one has to prove a quantum leap in hit and kill probability before anyone will take a new cartridge seriously.

So, what would define a quantum leap in hit and kill probability?

LR1955

[Tony Williams]

And I would say well over 90% of this is anecdotal and pure opinion. Lets see the empirical studies.

I would say that there are three types of evidence which can be taken into account:

1. An accumulation of anecdotes from soldiers in combat (one by itself means little, if there are lots which are mostly saying the same thing, then it's worth paying attention). Given the immense burdens that they have to carry, I don't believe that soldiers would be willing carry the extra weight of 7.62mm guns and ammo (as they are, in both US and UK armies) unless they were satisfied that it was worth it.

2. Laboratory tests (there seems to be some sort of objection to testing ammo on live people, so substitutes like ballistic gel need to be used for comparison). Fackler and Roberts have both demonstrated the poor performance of 5.56mm.

3. The many attempts to improve the performance of 5.56mm, including MK262, MK318 SOST, M855A1 (and, of course, the 6.8mm Rem). If M855 were satisfactory, why bother to put in all this effort to improve on it?

Bottom line is that one has to prove a quantum leap in hit and kill probability before anyone will take a new cartridge seriously.

Not necessarily, if there are also other reasons for considering a change (e.g. to get a lighter round than 7.62mm, and to get one standard round, as I mentioned). And not at all if you're adopting a new technology like LSAT, where you're starting from scratch with all-new guns, ammo and production lines anyway. Then you might just as well go for the best solution, which as ARDEC recommended would be 6.5-7mm, and as JSSAP seems to have accepted in rejecting 5.56mm LSAT. But we can't expect the US Army to go for an intermediate LSAT unless the performance of the calibre has already been demonstrated in conventional form.

[noone]

Anecdotal reports are discounted in drug testing, and other types of testing because they are so often biased. The only truly useful data will come from actual testing in both field conditions, and lab conditions. These tests must use not only gell, but also actual tissue such as pig or goat carcasses. By combining both the lab, field, and carcass testing, we can get a reasonably accurate prediction of how a bullet will likely perform.

However, this kind of testing is very expensive, and time consuming. Unless a military is already looking for a new cartridge, or if someone is interested in selling a new cartridge, this testing is very unlikely to be done just out of simple curiosity.

This type of testing also gets us away from hit probability as a factor. It is presumed that the bullet will performed based on placement. Trying to predict a bullet's effectiveness based on the varying degree of marksmanship that the troops demonstrate, is sort of like predicting who will win the Indy 500 based on driver's skill, without considering vehicle performance...or like predicting the race based on vehicle performance without considering driver performance.

If we presume the same amount of marksmanship, or drivers skill, in either case, the bullet with better performance, and the vehicle with better performance will be superior.

[LR1955]

I would say that there are three types of evidence which can be taken into account:

Laboratory tests (there seems to be some sort of objection to testing ammo on live people, so substitutes like ballistic gel need to be used for comparison). Fackler and Roberts have both demonstrated the poor performance of 5.56mm.

The many attempts to improve the performance of 5.56mm, including MK262, MK318 SOST, M855A1 (and, of course, the 6.8mm Rem). If M855 were satisfactory, why bother to put in all this effort to improve on it?

Not necessarily, if there are also other reasons for considering a change (e.g. to get a lighter round than 7.62mm, and to get one standard round, as I mentioned). And not at all if you're adopting a new technology like LSAT, where you're starting from scratch with all-new guns, ammo and production lines anyway. Then you might just as well go for the best solution, which as ARDEC recommended would be 6.5-7mm, and as JSSAP seems to have accepted in rejecting 5.56mm LSAT. But we can't expect the US Army to go for an intermediate LSAT unless the performance of the calibre has already been demonstrated in conventional form.

Tony:

How about a citation for the Fackler and Roberts test, the ARDEC and the JSSP reports? If you can, include the page numbers.

You ask "If M855 were satisfactory, why bother to put in all this effort to improve on it?"

Show me were the issued M-855 failed to meet its requirements when it was tested and accepted in the early 1980's? You know that it did met the requirements set for it and that these requirements were based on ground war against the Soviets in Europe. The requirements changed, doctrine changed, training changed, and so we adapted.

And, instead of going through an immense RDTE process, we bought commercial bullets that had already been tested via the mechanism of capitalism. And, they work!

LR1955

[JASmith]

My wife did a master's in school nursing a few years back. My own experience and education has been in the technical arena where testing and statistics means verifiable, repeatable and quantitative measurement. Imagine my shock and dismay when I found that much of the statistics developed in education and the psychological arenas are derived from anecdotal reports.

Yes, it appears that appropriate controls and qualitative measures can be imposed on a body of anecdotal reports so that they generate actionable insight. Biggest challenge is eliminating bias from the assessment.

I remember reading the gun magazines and books of the '50s when the .17 caliber craze first got started. There were discussions of the effect of the tiny bullet on donkeys. For example, a chest hit resulted in "the blood coming out as a single organ." It sounded like we had found a magic pill and my younger brother even bought one.

A long time and a fair bit of experience later I will admit I'm biased in favor of a larger bullet -- and that that bias is largely due to having seen a whole host of anecdotal reports from both the hunting and the military world. I cannot say, however, that my own reading and study is an appropriate statistical analysis.

[LRRPF52]

Jason Gillis, a former Army staff sergeant, first witnessed the M855’s shortcomings in 2004 on the streets of Baghdad. He was a squad leader with 2nd Brigade Combat Team, 82nd Airborne Division, on patrol when a vehicle began speeding toward his unit.

After several warnings, “both of our M249s opened up instantly, forming a crisscross pattern of tracer that met at the vehicles engine compartment and windshield. Within seconds, riflemen and grenadiers were executing magazine changes while the vehicle kept rolling and finally stopped 10 meters from my lead troops,” Gillis recalled in an e-mail to Army Times. He is now a freelance writer who often focuses on military small-arms issues.

“Assuming the driver was most likely riddled beyond recognition, we were all astounded to see the driver emerge from the vehicle completely unscathed,” Gillis wrote. “Closer inspection revealed that the M855 ammunition had failed to effectively penetrate the vehicle’s windshield despite the fact over 400 rounds were expended at extremely close range and on target.”

That was my Brigade. If I think he is who I think he is, I went to basic training with the guy 10 years before that. It makes sense that we were the same rank, but he must have been in another Battalion. Anyway, it doesn't surprise me at all that his SAW gunners lit up the engine compartment of the car and had no connection with the driver. The M4 and 203 gunners could have been dumping mags in a mad minute at the car all day long, but since they probably were shooting from a kneeling position or standing position in the scenario described for the 1st or 2nd time in their lives, I wouldn't be surprised if they weren't getting any driver hits.

You have to realize that at that time, we almost exclusively did marksmanship training from the foxhole supported, or prone unsupported positions. In addition, we would conduct some really lacking CQM (Close Quarters Marksmanship) drills run by people who usually didn't know anything about CQM, unless they had been to SOT while they were back in Ranger Regiment. Even if we did have guys who were subject matter experts in CQM and CQB, the command climate in my battalion was so screwed up that the SME's (Subject Matter Experts) were rarely given the opportunity to cross-pollinate their knowledge and experience in formal training sessions.

Even with the CQM training that I received, being a gun guy, having been through much more marksmanship training in several Scout Sniper Platoons, I couldn't hit the kill zone on a man-size target at less than 75m from a kneeling position with my RAS-equipped M4 during live-fire MOUT exercises, and one of my former Ranger Regiment Team Leaders under me couldn't either. I want to blame the loss of zero or barrel flex associated with the RIS, or something else, but the sad reality is that we didn't ever run marksmanship training that duplicated those scenarios and shooting positions, and practical marksmanship is one of the most perishable skills.

I'm pretty sure we weren't connecting on target effectively because we had the wooden mannequins that were suspended in the houses with 550 gut (the white string within paracord) that was run through a 4" hole and tied to a balloon in the dummy's stomach, wearing BDU's. You lean the target slightly so that a lot of pressure is on the balloon in his or her chest area, so that when a projectile sails through, the target reacts by crumpling to the ground. I have seen instances where during freezing temps, the balloons just don't deflate since they are frozen in their blown-up size, but several more hits will make them collapse enough to slip through the hole and the target will drop at least some.

Another indicator that day in my/our lacking in CQM abilities was that I couldn't even hit a half silhouette target at maybe 15m while moving from the woodline to the first shoot house, and I was supposed to be the leader of my Squad. Reason: I had never trained on shooting moving targets like that with my M4, because we were doing parades, trash pick-up, area beautification, guard duty, and spending more time in starched BDU's and highly-polished jungle boots. I got into USPSA and 3-gun shortly thereafter, and I could make those hits now easily with my pistol, but you see where I'm going with this...

Now ask yourself how many of those Joes had ever shot at a moving target under stress ("You're gonna die if that vehicle gets close enough to you!!!) from alternate shooting positions with IBA on and sleep deprivation. I'll tell you: They probably never did. We occasionally did exercises in the 82nd where these levels of performance were demanded or expected of us, but we had never really done any formalized CQM training to support the building blocks that need to be in-place before we could produce any acceptable levels of individual and collective performance in them.

Another caliber with more recoil and less mag capacity might have gotten them killed in the above-mentioned scenario if the poor driver had actually had a VBIED. My understanding is that there have been some fundamental changes in marksmanship training, the leadership climate, and the underlying culture that created a lot of these problems, but I'm not sure about the 82nd. That unit had some serious leadership issues in the higher echelons that severely limited junior leaders in taking risks or conducting enough realistic training. If you talk to any E-5, E-6, or E-7 who wasn't raised in the 82nd, you'll hear the same thing. The Joes are fresh out of high school, so they are like clay ready to be molded. Most of them are hard-chargers who want to take names and are very patriotic. Some of the officers we had were great leaders who were the same, but most seemed more concerned about their personal careers, were risk-aversive, and were content upon hiding behind the whole airborne mentality that supposedly made us better than our light infantry counterparts in 10th Mountain, 101st, 25th ID, and the few light units in 2nd ID. My experience was that we trained to our METL (Mission Essential Task List) jobs in those light units way more than we did in the 82nd, but were Airborne, you see...

It really came down to the leadership climate at Brigade, Battalion, and Company levels. Some Battalions had a former SF Battalion Commander and a Sergeant Major from CAG. I can tell you right now that those guys trained like it was real around the clock, and had a great time and were quite lethal in OIF1. If you had a non-performer for a BC, a reject for a BN SGM, you were pretty much suckin' when it came to training, unless your Company Commander and 1SG were gifted at conducting good training under battalion's noses, which is not likely. (Try hiding 150 swingin' Joes from the BN weenies...)

You see how this is not a caliber issue though...

LRRPF52

[BluntForceTrauma]

Liberty Ammunition has a video addressing the 5.56 vs. windshield issue: http://www.libertyammunition.com/Lead_Fr...RTY_T.html .

Of course, it's "sales and marketing" and not rigorous, unbiased testing, so take it for what it's worth.

I've seen a lot of dog and pony shows come and go. I think of how various gun makers heap mud or sand on their completely sealed AR and then pull the gun out of the mud or sand, shake it off, fire a few rounds, and we're supposed to be impressed that their weapon has passed some kind of extreme conditions test.

Glop mud or spray sand INTO the receiver and then we'll talk. . . . But I digress. . . .

John

[stanc]

Bottom line is that one has to prove a quantum leap in hit and kill probability before anyone will take a new cartridge seriously.

Gene, can you please cite a .mil document for that claim?

How about a citation for the Fackler and Roberts test, the ARDEC and the JSSP reports? If you can, include the page numbers.

Roberts http://www.dtic.mil/ndia/2008Intl/Roberts.pdf

p. 15 Gel tests (100 meters, thru glass)
p. 16 Wound profiles (bare gel)
p. 17 Gel tests (3 meters, thru loaded AK mag)

...instead of going through an immense RDTE process, we bought commercial bullets that had already been tested via the mechanism of capitalism.

Only partly true. In 5.56mm, the 77gr SMK has seen limited use, and the 70gr TSX, very limited use. However, an immense RDTE process was done to create M855A1 and Mk318.

[stanc]

IMO, some of the wound profiles shown below give a good idea of what's possible for non-deforming bullets.

To achieve early onset of yaw, it seems necessary to have rearward weight bias in the projectile. There appears to be two ways to achieve this:

1. A long-for-diameter, streamlined bullet -- such as 6.5 Grendel -- needs an air space in the nose. See 5.45x39 M74 profile for example.

2. In a short-for-diameter, not so streamlined projectile -- such as 6.8 SPC -- an air space in the nose in not so vital; the bullet shape seems to "want" to yaw relatively quickly after impact. See 7.62x39 M67 profile. (The Yugo M67 is a lead core, flat base bullet that is shorter than the original Russki M43 steel core, boat tail design.)

Terminal Performance

I have found only a few test results of 6.5mm and 6.8mm FMJ ammunition.
Awhile back, Silver State Armory tested a 6.8mm 101 grain "penetrator" that was reportedly of the same steel tip/lead core configuration as 5.56mm M855.

As shown above, the 6.8 FMJ (101gr M855-type) displayed pretty good terminal effects after punching through a thin steel plate. However, when fired into bare gel, wound profile was reportedly little or no better than for M855.

Attached: Gel tests of 6.5 Grendel 120gr FMJ and 6.8 SPC 115gr FMJ, both with lead core bullets. Note that the 6.5mm bullet was neither developed for the cartridge, nor designed to yaw, which explains the undesirably long (7") neck. The 6.8mm projectile had better (3") neck length, but still longer than the (>1") ideal.

Conclusion: Designing a streamlined, non-deforming, non-fragmenting, 6.5mm bullet that -- when fired at Grendel velocities -- will deliver terminal performance substantially superior to 5.56 NATO seems likely to be a great challenge.

[LRRPF52]

I just watched an interview with Mossad Ayoob back in 1990, where he was asked about which caliber/bullet is best for incapacitation. His response was that there is no such animal because there is no statistical, empirical baseline from which that question can be answered scientifically. He did say that he prefers the use of hollow points made to tight QC standards where bullet performance was predictable as far as velocity and expansion are concerned.

When I first saw the diagram displayed above, which is an artist's rendition of military assault rifle wound profiles dating way back (with added representations of Mk262 & 6.8 SPC), I remember how it contrasts with the large black book of forensic documentation of actual wounds that I studied back in 1998. This leads us back to the "no empirical data" position again. We can gel test all day long, but the gel tests don't incorporate bone or tissue segmentation which is fundamental to human and mammalian anatomy. They might give us a theoretical baseline from which to compare projectiles with each other, but how do we interpret that data to come to conclusions on what the projectiles will do on tissue?

Can we agree that the information is limited, but not totally useless? For example, when viewing this forum before the crash, I saw a lot of guys in the hunting thread say that they would never use the Nosler 100gr Ballistic Tips for hunting except on varmints, because it is basically explosive on tissue. Guess what my next purchase was? After I do some testing with the Nosler 100gr BT on certain mediums, it just might be in my bedside gun if I can reliably say that I have a significantly reduced capacity to endanger anyone beyond the intended target in a home defense scenario. Since the US uses the Hague guidelines, despite our signatory status, the Nosler BT is out of the question as far as I understand it.

Regarding rear weight bias projectiles such as the 7N6 (5.45x39mm original production), 7N10, 7N22, and 7N24, there are differences in the shape of the armor penetrator, but they all have a hollow nose cavity. The Russian guys I have spoken with who actually have used and do use AK74-based weapons in the Caucasus region said they had some problems with the 7N6 exhibiting radical ricochet characteristics that were lethal to friendlies, especially when supporting troops who were assaulting a building entry point, and the RPK-74 gunners and riflemen would lay down fire in front of the guys getting ready to go in. This resulted in the development of the 7N10 and higher projectiles that use a tungsten rod versus a sectional steel/lead core.

This is the design that interests me the most, and could be great for a barrier blind/tissue expansive device. Now find someone to manufacture such a bullet, test the prototypes, decide if it's worth pursuing, and move from there. If such a projectile could demonstrate a better of both worlds performance over M855, Mk262, and AP even, that would gain the military's attention, provided it could be done at reasonable costs.

LRRPF52

[stanc]

We can gel test all day long, but the gel tests don't incorporate bone or tissue segmentation which is fundamental to human and mammalian anatomy. They might give us a theoretical baseline from which to compare projectiles with each other, but how do we interpret that data to come to conclusions on what the projectiles will do on tissue?

Shoot hogs? That's what the 6.8 guys tout as the ultimate test medium, and (IIRC) the Swedes also shoot anesthetized pigs (in addition to ballistic soap) to test bullet performance.

Since the US uses the Hague guidelines, despite our signatory status, the Nosler BT is out of the question as far as I understand it.

So far. However, the USMC is currently using expanding bullets (Mk318) in Afghan combat, so perhaps someday bullets like the Nosler BT will be considered acceptable.

[LR1955]

Gene, can you please cite a .mil document for that claim?

Stan:

That gets into my personal experience with the RDTE system. If your cartridge only 'compares to' what ever it is intended to replace then you will not get anywhere as what exists is good enough. To get the attention of people, it must present a quantum improvement. What is quantum? In the early 90's it meant doubling hit probability and lethality to 300 or 500 meters (I can't remember which) given an 'average trained rifleman'. However it is my opinion that the Infantry School put this out because they weren't interested in going through another M-9 Pistol circus so they asked for something that couldn't be done to please Congress who insisted they bring up the lethality issue with the service rifle.

So, in reality the subject is much more than simply designing a cartridge and rifle that does everything and weighs nothing. If you want to get someone's attention, prove to them that your cartridge and rifle combination fired by an average rifleman can do everything you demand of it twice as well as what is already on hand. Do that and you have something going that may cause a change within the next ten or fifteen years.

That said, I sure do agree that a larger diameter bullet and more powerful cartridge should have been chosen in the late 1950's but it wasn't. Sure, a 6.5 or 7mm would have been a better bet but my bets are that even these two choices would be under severe criticism today for one reason or the other. If it wouldn't concern the weight of the ammunition it would be lethality or hit probability.

You see, no one will be satisfied with anything for long. Lets say we went to a 7mm which is something I would agree with like Tony. Within a few years as the novelty wore off and guys entered the service with no 5.56 experience, the complaining would start about recoil, noise, ammunition weight, over penetration / not penetrating enough / not penetrating and then being able to stop an African Elephant in full charge / not penetrating the frontal armor of a T-80 / not good for CQB / etc.

And I agree, the issued 855 is not a good choice for the type of doctrine and conditions we face today. However it was an ideal choice to meet the demands when it was designed and produced.

LR1955

[stanc]

Gene, nicely summarized. Thanks.

Stan

[RangerRick]

..., so perhaps someday bullets like the Nosler BT will be considered acceptable.

The plastic tip will have to go. One of the Hague Convention requirements is no materiel that is hard to spot in X-Rays.

[bwaites]

The plastic tip will have to go. One of the Hague Convention requirements is no materiel that is hard to spot in X-Rays.

That's an easy fix though, put some metal fragments in the plastic or use radioopaque plastics, they are cheap and easily done.

[JASmith]

The plastic tip will have to go. One of the Hague Convention requirements is no materiel that is hard to spot in X-Rays.

If I recall correctly, the Hague convention was originally enacted in an era where X-radiography was an emerging science. Is this a recent update?

Would it be possible to point us to the relevant paragraph in the current document?

[stanc]

If I recall correctly, the Hague convention was originally enacted in an era where X-radiography was an emerging science. Is this a recent update?

No. It's not in the Hague accords. It's the Geneva convention which bans bullet components that are X-ray translucent.

[JASmith]

... It's the Geneva convention which bans bullet components that are X-ray translucent.

Is there a link to the current version?

I wonder if any of our participants have enough background in interpretation of the law to do a non-binding pro bono review of the language and generate a summary of constraints? That review and summary could go a long way toward minimizing confusion and blunting wishful thinking.

The result would add relevance to the discussions and greatly assist Tony on his side of the pond and some of us on this side when we make our case to decision makers.

[LR1955]

No. It's not in the Hague accords. It's the Geneva convention which bans bullet components that are X-ray translucent.

Stan:

Don't tell me that we will walk this path again. Man, that topic went on for a while on the last forum.

LR1955

[JASmith]

LR1955

I believe we're interested in the same objective.

Absent a definitive summary of what is and is not allowed by the conventions, we fall prey to continuing speculation about "what if the bullet could..."

Tony's challenge is presenting a cartridge concept that will provide the desired effectiveness under the rules his nation is obliged to work under.

I see way too many references to US practice, including egregious extensions of that practice, in a thread motivated by UK and European needs.

So, the request for a more or less definitive summary is an attempt to keep the thread on track.

JASmith