Wound Profiles of Military Ammunition

[InfernoMDM]

Because of all the talk about AKs and ARs I thought some imagery to help look at balistics. Note the M855 Long NL which is the standard round the military shoots.

http://www.10-8forums.com/ubbthreads/postimages/40052-MilitaryAssaultRifleWPcopy.jpg

http://www.10-8forums.com/ubbthreads/postimages/40053-MilitaryRifleWPcopy.jpg

[nbk2000]

Ballistics (two L's) is the behaviour of a projectile during flight and in the gun.

Terminal effects is what the projectile does to its targets.

[InfernoMDM]

You are quite right, slip of the fingers/brain.

The 30 cm/12” line represents the minimum penetration distance necessary to consistently damage vital organs on larger individuals, with shots from oblique angles, and through intervening limbs. The 20 cm/8” mark gives a rough idea of the damage on an unobstructed frontal shot or on shots through thin, malnourished individuals.

NL refers to neck length—the penetration depth prior to initial projectile upset (yaw, fragmentation, deformation, etc…). The JSWB-IPT identified two issues that significantly alter projectile NL at CQB distances, thus causing differing terminal effects.

First, Angle-of-Attack (AOA) variability at impact can substantially wound severity; this factor is more prevalent with certain calibers and projectile types. Testing demonstrated that 5.56 mm is highly susceptible to AOA variations, particularly when using FMJ projectiles such as M193 & M855. For example, with 5.56 mm FMJ, at higher AOA’s, for example 2-3 degrees, bullets had a shorter neck length (NL) and upset rapidly, thus providing adequate terminal effects; at low AOA, like 0-1 degree, the projectiles penetrated deeper than ideal prior to initial upset (ie. long NL) with significantly reduced terminal effects. Note that other calibers were less susceptible to AOA variations than 5.56 mm and OTM’s tend to have less AOA issues than FMJ. The 6.8 mm has proved to have the least AOA inconsistencies of any caliber tested to date.

Fleet Yaw is the other significant yaw issue discovered by the JSWB-IPT. Fleet Yaw is the terminal performance variation caused by inherent variability in each rifle. 5.56 mm FMJ had the most Fleet Yaw induced variability of any projectile caliber & type. 6.8 mm had the least Fleet Yaw variations of any projectile caliber & type tested.

[B]What this means is that two shooters firing the same lot of M855 from their M4’s with identical shot placement can have dramatically different terminal performance results: one shooter states that his M855 is working great and is effective at dropping bad guys, while the other complains his opponent is not being incapacitated because M855 is zipping right through the target without upsetting. Both shooters are telling the truth…

[Hirudinea]

Seems rather strange that all this research goes into the "ultimate" bullet design because militaries have to respect an artifical limit in using fmj bullets.

[ShadowMyGeekSpace]

The M193 and M855 rounds won't do their little fragmentation trick below 2400fps. Using a barrel shorter than 14.5 inches isn't recommended, because then the round suffers greatly. Honestly, anything shorter than a 16 inch barrel isn't effective in 5.56 unless you're across the room from your target, and you're best with a 20 inch if you can manage it. There are also barrels machined ever so slightly smaller than the round size, so that the round builds more pressure and thus exits the barrel faster from the muzzle.

But really the 5.56mm round isn't that great of a round, I'd much rather purchase a 7.62mm upper reciever and use that instead of a 5.56 on an AR series rifle. If I was forced to use it though, I'd have each mag loaded with hornady tap rounds or hornady v-max rounds.

www.hornady.com

[Chris The Great]

See http://www.firearmstactical.com/wound.htm

This site not only diagrams like those shown above, but also includes a large selection of written resources on the subject.

[InfernoMDM]

See http://www.firearmstactical.com/wound.htm

This site not only diagrams like those shown above, but also includes a large selection of written resources on the subject.

I have been told about that sight a good bit from people who do ballistic and wound profiling for a living.

That sight has been quoted many times by different people on forums specifically to do with ballistics. None of the sights really like that sight for many reasons, such as faulty or misleading information. Then again these guys are dealing with the technical aspects, and the site is cut and pasting the information of research most times and not in the proper way.

[nbk2000]

Yes, that is an interesting web site. I've read that web site numerous times in the past. Hopefully it never drops out of sight, never to be seen again. ;)

[InfernoMDM]

Yes, that is an interesting web site. I've read that web site numerous times in the past. Hopefully it never drops out of sight, never to be seen again. ;)

I am sorry I have a learning disability my grammar issues are not due to laziness but my visual/reading comprehension skills being below par. I am a auditory learner. I know you guys love proper grammar here and its a challenge I have fought most of my life.

[nbk2000]

We don't expect perfect, but we do expect the effort to be made.

If you know you have a problem with spelling and grammar, use a word processing program to check your posts as much as possible before posting them.

Remember, the only person who your errors look bad on...is you.

And the concept of 'learning disability' is a liberal created excuse for laziness, and a government reason for mass-drugging of the sheeple's lambs. DON'T USE IT HERE.

[InfernoMDM]

We don't expect perfect, but we do expect the effort to be made.

If you know you have a problem with spelling and grammar, use a word processing program to check your posts as much as possible before posting them.

Remember, the only person who your errors look bad on...is you.

And the concept of 'learning disability' is a liberal created excuse for laziness, and a government reason for mass-drugging of the sheeple's lambs. DON'T USE IT HERE.

You know I was going to send this privately, but I am going to make this public. First of all where the hell is your PHD in Psychology? I bet you don't believe in PTSD or the difference between that and acute stress disorder.

Guess you don't believe in dyslexics.

Talk to me when you actually know something about the topic.

PS learning disabilities don't fall under the category of something you can medicate and go away. It's like being left handed.

I have installed software with Firefox to catch most of my errors which tend to be spelling.

Maybe before you go off half cocked on a subject you don't have any concept of go learn something about it. Over the years i have been around here just reading on and off I have seen several people jump down idiots who didn't know anything about a subject. Don't be a hypocrite.

[nbk2000]

What does Post Traumatic Stress Disorder have to do with ICQ Chat Dyslexia, which is the sloppiness of the mind upon contact with a keyboard?

And, no, dyslexia is NOT like being left handed, because there are plenty of southpaws who can capitalize the letter I when referring to themselves.

It's your mother language. If you can't be bothered to master it after so many years, what hopes have you for mastering anything here?

I didn't get further than the 9th grade, so what's your fucking excuse? :p

[InfernoMDM]

Your not a fucking PHD and you have no psychology degree of any kind do you? Which means before you spout off with, “And the concept of 'learning disability' is a liberal created excuse for laziness” pretty much is a bunch of shit. By the way grammar king if your so damn high mighty Mr. English major maybe you can tell me if starting a sentence with the word, “And” is acceptable in the English language. Maybe you should learn about a topic before spouting off about a topic you don't have the vaguest knowledge about.

The disability I have has nothing to do with being lazy, and it isn’t something that’s medicated.

Yeah it’s a sore spot, because I try very hard to make clear points online and my ability to express things aren’t up to standard.

Hell I was placed in a program for blind people and dyslexia audio books. College texts and the like come recorded so those who struggle to understand can listen and read along with the text. It hampers grades and makes life very difficult.

Just for instance as you read everything I typed its as if I spoke it to you. However when I read I read it

One

Word

At

A

Time.

The compression is there its just far more difficult for how my brain functions to get what I want to say, and how to say it on paper. Hence the problem with sight site etc. I focus on how it sounds on my head and cant complete wrap the difference around the different words. The definitions I understand, but as I proof read they both come out the same because they sound the same.

This has gone to far off course. If you have a problem with me fine I don't give a fuck, but don't be a hypocrite when someone gets on here and claims something is dumb and they don't know shit about.

[Alexires]

InfernoMDM - While I don't have a degree in jack shit, I have seen so many lazy cock suckers use the excuse of a "disability" to fuck around in class and still pass.

Understand where NBK is coming from, he probably has to deal with multiple people a month blaming their lazy asses on some kind of "disability".

Even if you don't understand where he is coming from, its still best to pretend you do and shut your mouth.

Also, making shit like that public doesn't win you brownie points, it just gets your "lysdexic" ass banned. If you aren't sure if it's the right word, or the right spelling, do what I do and use another word.



On topic, maybe someone could explain to me why some of those rounds seem to make 2 wound cavities inside the tissue? Other than the round tumbling, I can't think of a reason why there would be two cavities created a specific distance (about 10cm) from one another inside the body.

[festergrump]

InfernoMDM,

What exactly is your condition? Is it PTSD or Dyslexia? Both?

I fail to see any kind of correlation between your grammar problems and PTSD, and spellcheckers do catch Dyslexian slips like cops catch donuts...

You did mention that you have a spellchecker plugin for Firefox to correct your spelling mistakes, correct? Well, I've used several spellcheckers in the past when I had something very important to present to an audience, and every one that I've used might have let the site/sight mistake slip by, but NONE would have overlooked the un-capitalized "I" in post #11... the very post which you mention the plugin you have. So if you have it but don't use it... That, mister, is lazy.

My advice to you is simple. Apologize to the Forum for losing your cool, stop being lazy, and try to do better with your grammar in future posts. Alternatively, you could spontaneously combust here before the whole of the Forum (with another outburst on the matter, and much to the delight of members who enjoy such displays) and assume your position within the ranks of those who have been deemed worthless by the #1 slack reducer of this site, the Beast.


Alexires,

All the tests shown which resulted in dual cavity formations are labelled as from that of a FMJ round. Other FMJ rounds were shown only provide a single cavity formation, though. Therefore, I speculate that of all the FMJ rounds tested that DO show a double cavity formation in the gel, 100% of them have also a hollow cavity within the nose of the projectile (military round, Geneva convention 'getaround tactic' for severe damage without use of soft-point or hollow-point ammo) which causes it to tumble on impact (like you mentioned), whereas the FMJ projectiles that show only one large cavity are solid through and through to the jacket (production for civilian usage, airborne lead reduction at ranges).

My thoughts are that the first cavity should be that of the jacket seperation or disintegration and the secondary that of retained core-weight on a tumble. Any resulting penetration beyond the secondary cavity should be that of the projectile resting in an ass end first position (likely) and carrying it's weight throughout the tissue resistance until energy is lost entirely.

Those FMJ projectiles which do not exhibit dual wound cavities likely do not experience jacket seperation to the extent of their empty-nosed cousins, thus one wound cavity?

One would have to learn more about each round tested besides just it's place of origin, weight, and FPS to verify this, though, or it's simply a theory drawn from somewhat self-educated guesses...

[FUTI]

AFAIR first cavity is created by some drill-like action of round while slowing down inside the balistic gel (or body) since it starts loosing its balance due to slowing down at certain point, but it then correct its path and go straight for a while until its velocity drops to a level where it again loose its balance and starts thumbling and in the end it continue traveling its wider end first and its tip following it.

I think that I read somewhere article about that where it is stated that a soldier hit with such round in the torso can expect that round will exit with its wider end (or base or whatever they call it) first...that should be memorable exit wound. They design it that way on purpose because there is a big pressure to ban by Geneva convention all rounds that can fragment inside the body to augment lethal effect...but none said anything about yaw or blast effects etc., so go figure ;).

Fester is correct Russians make hollowpoints on their 5,45mm round IIRC, but that isn't the only way you can get that thumbling effect. You just need to fine tune the center of gravity of that round (which can be made with an air bubble among the other ways). Anyway this isn't my field...so I have something to ask. I found a claim about reason why Russia made hollowpoints an ammo of choice for their 5,45mm round - it is claimed as more effective against personel armored vest infantry use today. Is that a bullshit or it has some grain of truth in it?

Thanks for the link its a long time I read anything about this. I find an info about AOA for 6,8mm ammo a treasure. Ripped from this site 'http://world.guns.ru/assault/as86-e.htm'. Although it used 6,5mm round it is close enough to the story of ideal round. If you guys search that you must look upon the old stuff when people looked upon those balistic properties with more attention, before they go with happy-trigger-finger tech approach. "Despite these flaws, it was a formidable and historically important weapon, and, ironically, its ballistic properties are very close to modern idea of "ideal" assault rifle and its ammunition."

Anyway it seems that Russians won't quit their 7,62mm round they even consider going back to it. I just seen two days ago on web info about new version of AK with famous old 7,62mm.

[InfernoMDM]

nbk2000 - I would have gladly said I was sorry until you inferred that I was lazy messing up because I was lazy. I don't think you are a bad person and I have no bit of contention with you as obviously you have had this problem with others. I just ask you to realize that some of us do have a learning disability, and don't mind being corrected. It helps us catch ourselves, but many people with this issue like people to understand so we don't have accusations brought upon us by people who don't understand. I have PMed the other two to explain my point. If you still have a issue PM me as the topic went far enough off track, which was my fault.

The two wound cavities are from the exact same bullet in theory and practice. I am going to quote the technical info posted on another site I frequent because my attempts at explaining it in normal terms might loose something, and like I said my ability to communicate in text isn't as wonderful as it should be. After that I will attempt my own interpretation and any faults in my train of thought should be more easily corrected.

Question
Could you please explain what physical differences between individual rifles that constitutes inherent variability, and why this creates dramatically different results. What I'm trying to wrap my head around is what physical differences in rifles (inherent variability)causes fleet yaw to occur.

Reply
While the concept of Fleet Yaw is new to me, the factors that Doc stated are not. Two apparently identical rifles will still have minute variations in the quality of their rifling, barrel harmonics, bolt lockup, etc. As a consequence, one may shoot very well with a particular load, while the other does not and needs something a bit different. That is why you can't depend on someone else's experience with a particular load to predict a duplicate performance in your gun.

In retrospect, it should have been obvious that if the same load can group differently in an otherwise "identical" rifle, then the critical bullet performance can vary as well.

The Ammo Oracle on AR15.com has pretty good info. They give velocity parameters/bullet performance for M193 and M855 ammo. However, Fleet Yaw makes that more of a general assumption than a hard border.


Joint Service Wound Ballistic Integrated Product Team: “In response to inquiries from the field, the Army’s Project Manager, Maneuver Ammunition Systems (PM MAS) has assembled a team of experts from many disciplines including military users, law enforcement, trauma surgeons, aero ballisticians, weapon and munitions engineers, and other scientific specialists to answer the question--Are there Commercial Off-the-Shelf 5.56mm bullets available that are better than M855 “Green Tip” against unarmored targets in Close Quarters Battle (CQB)?”
Very little accurate public information has been released, but you might wish to review: http://www.dtic.mil/ndia/2004arms/session9/minisi.ppt (Warning, this is a VERY large file)

The JSWB-IPT recently discovered that Lake City has manufactured TWO distinct types of M80 FMJ over the last several decades, one using a thick copper jacket that does not fragment, as tested by Dr. Fackler at LAIR and another previously untested version using a steel jacket that fragments at velocities above approximately 2800 f/s. Yaw and fragmentation occurs at about the same penetration depth as with copper jacket M80, and is thus deeper than ideal (ie. NL too deep). When the velocity drops to below 2800 f/s (by approx 100 m from 22” barrel M14), M80 steel jacketed bullets no longer fragment and instead act like the non-fragmenting copper jacketed M80 FMJ.

Fleet Yaw and the effect it has on identical rounds.
Fleet Yaw is caused by weapon to weapon variations. Projectile impact AOA variability is caused by bullet to bullet variations. Both appear much more prevalent in 5.56 mm, particularly with FMJ loads, than with larger calibers and match loads. These are clearly multi-factorial problems of multiple etiology including: ammo and weapon design issues, ammo and weapon manufacturing variations, individual weapon wear issues, along with both mechanical function and internal ballistics variances.

Questions 2-3
A few key questions:

1. Is this fleet Yaw difference something that only occurs with the M855 62 grain load?

2. Is it a difference between different manufacturer's M-16s or among individual M-16s?

Answer
Although the concept of fleet yaw and other variables in ammunition is interesting and should be kept in mind, I think some here are worrying about minutia when talking about real-world application of the tools of the trade. Pole-vaulting over mouse turds so they say...

Precision shooting, although not the topic of this discussion may help illustrate a point. Precision shooting involves isolating and eliminating as many variables as possible: To compensate for, or eliminate changes in the platform, optics, ammunition, human interface or environmental concerns from one shot to the next. To make each shot "just like" any other shot under like conditions, as a predictor of point of impact.

Why is it so hard to believe that mass produced ammunition and weapons would exhibit a degree of variability, even when produced to a known, certified and quality controlled specification?

When these tolerance variables are combined and stacked upon one another (like "soft" optics mounts on out-of-spec bases Evil), it is given that certain variability in terms of accuracy and terminal ballistics will be the end result.

Add to all that the fact that the human animal will exhibit different physiological and psychological stamina from individual to individual. How about my "torso" shot versus another shooters "torso" shot? - target angle, elevation, physique, etc. In some ways it is as much art as science. Not everything can be number crunched into simple 0s and 1s. But we can predict performance.

The concern should not be if you have the "right" lot of ammunition or the "best" carbine from a lot proven to be a known man-killer. The concern should be placing rounds into your intended target until it is no longer a threat.

Doc will correct any errors I make here, but here is some short background on M855 and why I don't like it. When M855/SS109 was developed, we were still looking at the Red Army coming through the Fulda gap. It was developed for the SAW, which accounts for two of its characteristics. Inconsistent bullets and penetrators. One of the features touted for SS109/M855 is the penetrator and its greater penetration of hard targets at extended ranges than say M80 7.62mm. When I first read the specs I had to shake my head. Penetration of a Soviet helmet at 600m? WTF!! A soldier with an M16A2 iron sights can't see a helmet at 600m, so who cares if the bullet will penetrate? Still true I think, but when you are talking about a SAW putting out a cone of fire, that accidental hit becomes much more likely and of greater validity.

Cone of fire. This is for the unmilitary, not the BTDT. You don't normally want nice tight groups from a MG. You want a cone of fire, analogous to a shotgun pattern. You want a spread to a degree so that if 2 bullets miss at 600m, maybe that 3rd one hits and maybe 5 or 6 hits the guy next to him. Inconsistencies in the bullets will help accomplish this because bullets won't fly the same way.

These were reasons I have chosen not to purchase M855 for my own use. It is generally less accurate than M193, primarily due to inconsistencies caused by the steel penetrator. Because it is a heavier bullet, muzzle velocity is less. Fragmentation is largely dependent on velocity, so effective fragmentation range is less than M193 for any given barrel length. And, at closer distances, the higher MV of M193 actually results in superior armor/barrier penetration. Only at extended ranges does the M855 offer superior retention.

Again, as I understand it, Fleet Yaw occurs with all weapons and all calibers.

quote:
Fleet Yaw is the terminal performance variation caused by inherent variability in each rifle. 5.56 mm FMJ had the most Fleet Yaw induced variability of any projectile caliber & type. 6.8 mm had the least Fleet Yaw variations of any projectile caliber & type tested.



If you have quality barrels made to the same spec by the same manufacturer, with caliber being the only difference, then the barrels themselves should be producing the same amount of Fleet Yaw. The rest of it should be attributable to the bullet and cartridge itself. Quality/consistency of the brass, primer, powder, bullet components & construction and chamber to case fit all have an effect.

Doc didn't mention testing M193. Nor did he mention other calibers or loads in his statement about different results from different rifles. Give him a break, he was answering a question, not writing a book!

Since the principal of Fleet Yaw is universal to all calibers and barrels, the effect is there for all. It just appears that for the loads described here, M855 exhibits the most.

Here is my interpretation. Essentially because these rounds vary in velocity upon impact, and Angle of Attack(see above about AoA) we see two different wound cavities.

This is caused by the round not yawing on impact. That means if it doesn't have a steep enough AoA or the bullet isn't traveling fast enough the round will not being to rotate in the body.

Also the break down of the round varies due to minor changes in the jackets strength as well.

http://www.dtic.mil/ndia/2004arms/session9/minisi.ppt (Warning this is a large file)

[nbk2000]

By the way grammar king if your so damn high mighty Mr. English major maybe you can tell me if starting a sentence with the word, “And” is acceptable in the English language.


Genesis 6:17 KJV


And, behold, I, even I, do bring a flood of waters upon the earth, to destroy all flesh, wherein is the breath of life, from under heaven; and every thing that is in the earth shall die.

So, yes, I can start a sentence with the word 'And'. :)

Maybe you should learn about a topic before spouting off about a topic you don't have the vaguest knowledge about.

[akinrog]

Genesis 6:17 KJV


And, behold, I, even I, do bring a flood of waters upon the earth, to destroy all flesh, wherein is the breath of life, from under heaven; and every thing that is in the earth shall die.

So, yes, I can start a sentence with the word 'And'. :)

Maybe you should learn about a topic before spouting off about a topic you don't have the vaguest knowledge about.


Sir,

since the text in bible is originally in Hebrew, it's totally different language and as far as I remember it's grammatically wrong to start a sentence with "AND" or "BUT" in English, although many of us do the same frequently.

However I like the allusion to original poster. :D

[nbk2000]

I was just quoting myself. ;)


And, behold, I, even I, do bring a flood of electrons upon the Forum, to destroy all k3wLz, wherein is the breath of membership, from under My heaven; and every k3wL that is on the Forum shall die.

[Alexires]

"And where God did destroy the Tower of Babel, and caused all men to speak a thousand tongues, NBK rebuilt the Tower of Babel and challenged the might of the lord, causing all manner of men to speak in the one true tongue." - The Book of NBK.

Interesting how you could look at a lot of topics in the bible and the exact opposite happens here. Where Moses (as the instrument of God) seeks to part the red sea, we seek to make a red sea (as in Blood red). Where God brings the Prophet to the mount, we bring the mount down on top of the Prophet.

Where the bible is full of contradictions, we seek true knowledge (whatever that may be) and cast ourselves as the Gods of our own universe.

Revelations (Apocalypse), Chapter 16:

"....Go and pour out the seven vials of the wrath of God upon the earth."

Whats to bet God synthesized those in his lab from OTC ingredients?

[I probably hate you]

Infernomdm you did'nt seem to know much about the wound profile of the m855 the other day when I posted a link about ballistics , now you are an expert . I decided that instead of probably hating you I do . I just wanted to add you metioned me getting the kewl totse treatmeant at other sites if I shared my knowlage , well look who is getting grilled here with you kewl coping BS go away ! The reason , by the way , others (forum rambos) dont like that sight is they go by science and real world wound ballistics (not your shit forum crap) notice the main contributer was a battle field surgen , not washed up bacon .

If you have read this sight so much why the fuck are you being so belligerant get a clue and swallow your pride when it is needed or you will be on the fast track to being BFL . A little critisim is'nt always a bad thing learn from your mistakes and quit making them . Otherwise you could read up and make some HE and not learn from those mistakes and do me a favor .

[knowledgehungry]

Interesting how you could look at a lot of topics in the bible and the exact opposite happens here. Where Moses (as the instrument of God) seeks to part the red sea, we seek to make a red sea (as in Blood red).


I don't believe that that is the intended purpose of this forum:cool: .

NBK that post quoting God was one of the funniest things I have read in a long time.

As far as the ammunition goes I believe that civilians can actually use better ammunition than the military(in terms of expansion). Civilians can buy hollowpoint ammo, and IIRC the military is required to use FMJ.

[nbk2000]

Ah, but if we started discussing the wounding potentials of civilian ammuntion, we wouldn't be talking about military ammuntion anymore. :(

But let's not let that stop us. :)