Small Caliber Lethality: 5.56mm in CQB
- Thread starter Bartholomew Roberts
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gearhounds
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They're kind of working on that with the 6.8mm; I don't see the entire inventory being rebarrelled though.
Oh, and for those advocating universal use of expanding or hollow point bullets for general infantry use, consider that frequently soldiers are shooting at targets through barriers such as windshields, doors, walls, body armor and the like. Expanding bullets are much less useful than FMJ bullets in such situations.
Not to mention, having enough rounds to fire so that your buddies can maneuver is another aspect of 'effectiveness.'
Good article. Finally explained the 'yaw' phenomenon I've heard so much about. If true (and it looks like it is), it would explain why some 5.56's annihilate the target while others zip through.
Good article. Finally explained the 'yaw' phenomenon I've heard so much about. If true (and it looks like it is), it would explain why some 5.56's annihilate the target while others zip through.
Csmsss: I offered no "evidence" and barrier penetration is an entirely different topic (where I would still choose a .30 bonded bullet over a 5.56 any day). You don't need to wax modus ponens to see that the jury is evenly split and hopelessly deadlocked... which is why I suggested hedging your bet with the larger round. Geez Leweez!!
KChen: The number of projectiles in the air is not a characteristic of the round itself, so no... it isn't another aspect of effectiveness. IIRC the MG 42 (8mm) cyclic rate was about 300 rpm faster than the M16, just say'in...
KChen: The number of projectiles in the air is not a characteristic of the round itself, so no... it isn't another aspect of effectiveness. IIRC the MG 42 (8mm) cyclic rate was about 300 rpm faster than the M16, just say'in...
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First I will defer to those who have used them in combat.
The thought that I had was from watching it's inception on the History Channel. Eugene Stoner was trying to sell this to the military. They showed a 55 gr. bullet hit a block of geletan at 150 yards, and the bullet turned 180 degrees inside causing a lot of damage.
Stoner gave a demo at a 4th of July picnic by shooting a watermelon at 150 yards with impressive results. Air Force General Curtis Lamay was there. He ordered some for military use.
The war that we are presently in involve longer distances. The American Rifleman Magazine said recently that they were bringing out M-14s out of storage to be more effective at the longer ranges that our soldiers must deal with. The M-14 is 308 or 7.62 NATO.
The thought that I had was from watching it's inception on the History Channel. Eugene Stoner was trying to sell this to the military. They showed a 55 gr. bullet hit a block of geletan at 150 yards, and the bullet turned 180 degrees inside causing a lot of damage.
Stoner gave a demo at a 4th of July picnic by shooting a watermelon at 150 yards with impressive results. Air Force General Curtis Lamay was there. He ordered some for military use.
The war that we are presently in involve longer distances. The American Rifleman Magazine said recently that they were bringing out M-14s out of storage to be more effective at the longer ranges that our soldiers must deal with. The M-14 is 308 or 7.62 NATO.
Problems I have with the article itself....
Vertical axis of graphs are simply labeled "higher" and "lower" without any reference data or scale.
Of all the ammo supposedly tested only M80 ball (147gr FMJ 308) was put into the charts alongside the 5.56 candidates.
The measurement of effectiveness was listed as "permanent wound channel" and yet 55 grain FMJ 5.56 has the same lethality as M80 Ball even out to 100 meters? Either the graph has scaling problems or something else is fishy.
Don't get me wrong, I don't have any problems with the article, but it is hardly "scientific" by any stretch. And relying on "bullet yaw" to provide the mechanism for lethality seems like it is in direct conflict with accuracy...
Jimro
Vertical axis of graphs are simply labeled "higher" and "lower" without any reference data or scale.
Of all the ammo supposedly tested only M80 ball (147gr FMJ 308) was put into the charts alongside the 5.56 candidates.
The measurement of effectiveness was listed as "permanent wound channel" and yet 55 grain FMJ 5.56 has the same lethality as M80 Ball even out to 100 meters? Either the graph has scaling problems or something else is fishy.
Don't get me wrong, I don't have any problems with the article, but it is hardly "scientific" by any stretch. And relying on "bullet yaw" to provide the mechanism for lethality seems like it is in direct conflict with accuracy...
Jimro
Bartholomew Roberts
Moderator
Eagle0711 said:
This paper was only about effectiveness in CQB. Even the authors state that you can't extend these conclusions to longer range. I'd really prefer not to get into the longer ranged discussion because we have to discuss a lot more concepts that aren't really relevant to this particular topic and most of us aren't going to be using 5.56 at those distances anyway.
Jimro said:
The data was gathered from the JSWB-IPT review of 5.56mm ammo. I don't think all of that information is available to the public, which may be why the graph lacks a more specific reference.
Yes, because the purpose of the study was only to determine if there was a "drop-in" COTS replacement for M855 that would improve performance significantly. The M80 ball round was added only as a reference point/control.
Actually, it makes perfect sense. 5.56mm will tumble and fragment inside 100m usually. As it fragments, it perforates the stretched temporary cavity and causes some of those tissues to become detached and part of the permanent cavity - kind of like stretching a rubber band while simultaneous poking little holes in it with a needle.
M80 ball tumbles also; but it takes longer to do it and it doesn't fragment. It does have a much bigger temporary cavity; but unless it stretches something past its elastic limits, it will just snap back into place. The blocks of ballistic gel used in testing are more than capable of containing that temporary cavity.
So 5.56mm is roughly equal (actually better by some measures) under 100m because it is able to convert part of its "temporary cavity" to permanent cavity via fragmentation in ballistics gel; but M80 ball is not able to do this.
It isn't in direct conflict with accuracy at all. For one, it is much easier to spin stabilize a bullet in air, than in tissue. So a bullet that is perfectly stabilized or even overstabilized in air, will still upset in tissue.
The problem with relying on bullet yaw for good effect is the one shown in that article. The nose of the bullet is basically wobbling like a football all throughout flight - although it is a very tiny wobble, where it is in that wobble when it hits the target plays a big role in whether M855 or M193 penetrates 4-5" before yawing or yaws immediately.
So let's say you are shooting at a guy behind a wood wall - the bullet hits at high yaw and begins fragmenting, causing it not to penetrate deep enough and guy shoots back. You then turn and shoot at guy standing in open; but now bullet hits at low yaw and zips right through him before tumbling. In both cases, you get an undesirable result that you have minimal control over (other than using controlled pairs to improve the odds you get good yaw).
On the bright side, neither the new Mk318 used by the USMC or the M855A1 are dependent on yaw.
The article reflects a lot of new research in terminal ballistics, though it does slant towards 5.56x45 by using only M80 ball for reference, even though JSWB-IPT tested 6.5 and 6.8. It also limits the discussion to frontal, unobstructed, unarmored, CQB which also happens to be where M855 has the most advantages.
Bartholomew Roberts,
Don't **** on me and tell me it's raining. Take a look at the wound cavity volumes posted here, because M80 can and will fragment at close range (Dr. Fackler noted German 7.62x51 bullets for their fragmenting ability) . Now, even if they took data from a non-deforming 308 round they still listed it as "higher" than any of the 5.56 offerings.
55 gr M193 will "normally" fragment out to about 150. I know this, understand this, and don't have a problem with it.
M855 will normally fragment inside 75. The reduced velocity of the heavier pill and shorter M4 barrel make this a good "guestimate."
So listing all this data in one homogeneous fuzzy catepillar across the top means that there is something wrong with the scaling of the graph.
The point is that you can design a study to get the result you want, and without showing your data sources to prove that you didn't do that you lose credibility. The book "Study a study and test a test" is written about medical research, but the techniques for critical thinking apply here as well.
Jimro
Don't **** on me and tell me it's raining. Take a look at the wound cavity volumes posted here, because M80 can and will fragment at close range (Dr. Fackler noted German 7.62x51 bullets for their fragmenting ability) . Now, even if they took data from a non-deforming 308 round they still listed it as "higher" than any of the 5.56 offerings.
55 gr M193 will "normally" fragment out to about 150. I know this, understand this, and don't have a problem with it.
M855 will normally fragment inside 75. The reduced velocity of the heavier pill and shorter M4 barrel make this a good "guestimate."
So listing all this data in one homogeneous fuzzy catepillar across the top means that there is something wrong with the scaling of the graph.
The point is that you can design a study to get the result you want, and without showing your data sources to prove that you didn't do that you lose credibility. The book "Study a study and test a test" is written about medical research, but the techniques for critical thinking apply here as well.
Jimro
There was a test conducted by some interested Australians in regard to some details of the Kennedy assassination that made interesting viewing. But these comments are about the cartridge and the bullet, not assassination theory.
The rifle was a 6.5mm, near enough to some of the latter day small bore wonders that some would like the army to adopt. Somehow they managed to find a box from the very same lot, which is something but is beside the point. They fired a few rounds at a carefully built anatomically correct (mostly, anyway) dummy, attempting to replicate the bullet path. They also fired the same round into a wood post.
While I think newer rounds are probably going to be lighter than the old fashioned 6.5mm Italian service round, the curious thing is that in all the tests, the recovered bullet (including the one that penetrated about three or four feet of solid wood) was virtually unmarked except for the rifling. They also fired one into geletin and it demonstrated an impressive wound channel, if that's important. And all of that with a full metal jacketed bullet.
But it wasn't a close quarter battle rifle by any means. For that I assume they preferred a submachine gun in 9mm. And I know what people think of 9mm.
The rifle was a 6.5mm, near enough to some of the latter day small bore wonders that some would like the army to adopt. Somehow they managed to find a box from the very same lot, which is something but is beside the point. They fired a few rounds at a carefully built anatomically correct (mostly, anyway) dummy, attempting to replicate the bullet path. They also fired the same round into a wood post.
While I think newer rounds are probably going to be lighter than the old fashioned 6.5mm Italian service round, the curious thing is that in all the tests, the recovered bullet (including the one that penetrated about three or four feet of solid wood) was virtually unmarked except for the rifling. They also fired one into geletin and it demonstrated an impressive wound channel, if that's important. And all of that with a full metal jacketed bullet.
But it wasn't a close quarter battle rifle by any means. For that I assume they preferred a submachine gun in 9mm. And I know what people think of 9mm.
Bartholomew Roberts
Moderator
Jimro said:
First of all, West German 7.62x51 isn't the same thing as M80 ball - just as SS109 isn't the exact same thing as M855. The reason the West German 7.62x51 fragmented was that it had a thin jacket relative to M80 ball. We're talking about a specific ammo type here, not all 7.62x51 ammo.
Second, the link you just provided states that M80 ball can fragment IF it is travelling in excess of 3,000 fps. A typical 20" barrel launching M80 ball is only going to produce about 2,800fps. So short of shooting someone at contact distance with an M40A1, you aren't likely to see fragmentation from M80 ball.
Third, even if M80 ball did fragment, you'll notice that the link you provided shows it starts to yaw at around 20cm - if you are looking at frontal, unobstructed target (as this study did), the M80 ball will exit just as it starts to tumble - meaning the bigger temporary cavity is pretty much wasted.
Actually, if you'll zoom in on Figure 3, you'll see that the 5.56 round from the M16A2 marked as "--X--" starts out the highest on the chart. I'm not sure where the M80 ball is on that chart because there doesn't appear to be any symbol for it on the key.
Figure 8 showing the comparison of controlled pairs and single shots shows the M16A2 M855 as most effective, with M855 out of an M4 and M80 out of an M14 being roughly equal.
Also by zooming in, I noticed "Further dissemination only as directed by Office of the Project Manager, Maneuver Ammunition Systems, or higher DoD authority" which seems to suggest that the scale and other details may not be for public consumption.
However, if you want a good, informed criticism of this article from someone who would know the numbers on that scale very well, DocGKR (who has been in the midst of a lot of this research) posts a critique of this article at M4Carbine.net.
Bartholomew Roberts,
Either you are the ultimate 5.56 fanboy or you are selling something. Either way I seem to be arguing that the data was not presented in a manner consistent with scientific rigor. And your reply has been that 5.56 is great and the numbers are not for public consumption. Which means that you agree with me that the article as written is not rigorous.
Jimro
Either you are the ultimate 5.56 fanboy or you are selling something. Either way I seem to be arguing that the data was not presented in a manner consistent with scientific rigor. And your reply has been that 5.56 is great and the numbers are not for public consumption. Which means that you agree with me that the article as written is not rigorous.
Jimro
Bartholomew Roberts
Moderator
I think your criticisms of the article are ill-informed. There are plenty of places to criticize it; but the ones you have chosen make no sense to me.
BR,
They set up a classic comparison study, then hide more than half the data. The data that they do release is put on a scale of "higher to lower" without any reference data and the scaling clusters the data into a fuzzy caterpillar.
Those are legitimate points of contention. If I presented research that manner I would be rightly ridiculed and told to do it again.
And as for the 5.56 being an adequate CQB round? That isn't a surprise, pretty much any modern rifle cartridge is perfectly adequate for CQB. Heck, even a 30-30 with a soft nose blunt bullet gives a more impressive cavity than most FMJs.
Jimro
They set up a classic comparison study, then hide more than half the data. The data that they do release is put on a scale of "higher to lower" without any reference data and the scaling clusters the data into a fuzzy caterpillar.
Those are legitimate points of contention. If I presented research that manner I would be rightly ridiculed and told to do it again.
And as for the 5.56 being an adequate CQB round? That isn't a surprise, pretty much any modern rifle cartridge is perfectly adequate for CQB. Heck, even a 30-30 with a soft nose blunt bullet gives a more impressive cavity than most FMJs.
Jimro
Bartholomew Roberts
Moderator
Except in this case there isn't any question that the research was done or peer-reviewed since it based on the JSWB-IPT research. The article is broadly outlining research that DoD has not yet chosen to release.
And the conclusion doesn't strike me as especially shocking - all 5.56mm COTS drop-in replacements for M855 (which I presume means land warfare legal) tested perform about the same from 0-50m. So even though I'd agree that a comparison with no scale lacks utility, I don't really see why the conclusion is unbelievable.
The points I thought made good discussion were a deeper explanation of how the yaw mechanism works and why it fails at times as well as showing how multiple shots significantly increased the odds.
With a literary maneuver you dismissed this gentleman’s experience as “anecdotal”, but it is the gentleman’s experience. He actually shot people or saw people shot with the .223 and they ran off.
How many people have you shot with your .223? How was the effectiveness? Did you perform an immediate autopsy and write a technical report on each incident?
WhiskeyTango’s actual combat experience is far better than the paper theories of internet Commandos, and enough of these experiences have surfaced to have the .223 reexamined again. The .223 is a marginal combat round, the Vietnam generation had this same issue, this generation of Soldiers rediscovered it, and the next generation of Soldiers who use the .223 will discovery it once more.
As for this article from the Infantry Magazine, It did what it was supposed to do, reassure the soldiers that their weapons “are the best”:
Reassure that the Cadre that their weapons are best, their leadership is best, everything is best, whether or not they are the best. In short the Army Leadership will mislead/lie in order to keep morale high within the ranks. Myth and superstition indeed! They do it all the time. Read any Army publication, from any period. You would think that we won the Vietnam War, the war in Iraq, and are winning the war in Afghanistan.
And if their weapons are so perfect why is the armaments community working to find something better?
Soldiers have to be very careful not to say anything that might be constructed as negatively affecting the morale of troops as to do so is subversion. So why should anyone expect to read anything but Morale boasting puff pieces in Armed Services Journals?.
18 USC CHAPTER 115 - TREASON, SEDITION, AND SUBVERSIVE
Sec. 2387.
(a) Whoever, with intent to interfere with, impair, or influence
the loyalty, morale, or discipline of the military or naval forces
of the United States:
Bartholomew Roberts
Moderator
Slamfire said:
I didn't dismiss it. I appreciate any information I can get, especially from the source. It is however anecdotal. And if you read the original poster's statement, one of the problems in that anecdote is that two people standing there who both saw the shooting can't agree on whether the target was even hit.
Now personally, I don't think that makes a good basis for forming an opinion; but if you want to hang your hat on that rather than my "internet commando" comments, then you're welcome to do it.