That was a good post Grumpy.
Sure as hell ain't the "Hammer of Thor" as some would like you to think.
Just more deceiving propaganda aimed at the American public.
Thanks BRL;
Here's some more information along those lines. Still can't find the original Navy study, but it was part of a larger joint services thing and the pdf link is to a presentation on that. AOA is "angle of attack" and refers to the angle between the bullet's axis and its path of flight. Essentially the 5.56 is more prone to precessing like a top around its flight path due to the very small diameter and the manufacturing tolerances in both gun and cartridge. A small angle (2-3 degrees) is enough to induce early "upset" (yaw cycle initiation) and produce those freak wounds that doctors who want to ban the 5.56 love to seize on and that those who want to kill the .308 and 6.8 in military service also love to harp about. Problem is that this wounding mechanism is not reliable in a FMJ 5.56, nor does it "work" at longer ranges. .308 and 6.8 do, and its notable that at ranges exceeding 200 yds the .308 US M80 ball loading is actually travelling faster than the 5.56 M193.
http://www.dtic.mil/ndia/2008Intl/Roberts.pdf
One particularly notable quote from the JSWB-IPT presentation:
"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 opponents
are not being incapacitated because M855 is zipping
right through the targets without upsetting. Both
shooters are telling the truth…"
Here's a quote from Dr Martin Fackler on the topic of 5.56x45 M193 ball. Unlike the civilian doctors interviewed by CNBC, Dr Fackler was a US Army Surgeon in VietNam and saw more than his share of wounds from rifle fire.
"In 1980, I treated a soldier shot accidentally with an M16 M193 bullet from a distance of about ten feet. The bullet entered his left thigh and traveled obliquely upward. It exited after passing through about 11 inches of muscle. The man walked in to my clinic with no limp whatsoever: the entrance and exit holes were about 4 mm across, and punctate. X-ray films showed intact bones, no bullet fragments, and no evidence of significant tissue disruption caused by the bullet's temporary cavity. The bullet path passed well lateral to the femoral vessels. He was back on duty in a few days. Devastating? Hardly. The wound profile of the M193 bullet (page 29 of the Emergency War Surgery-NATO Handbook, GPO, Washington, D.C., 1988) shows that most often the bullet travels about five inches through flesh before beginning significant yaw. But about 15% of the time, it travels much farther than that before yawing-in which case it causes even milder wounds, if it missed bones, guts, lung, and major blood vessels. In my experience and research, at least as many M16 users in Vietnam concluded that it produced unacceptably minimal, rather than "massive", wounds. After viewing the wound profile, recall that the Vietnamese were small people, and generally very slim. Many M16 bullets passed through their torsos traveling mostly point forward, and caused minimal damage. Most shots piercing an extremity, even in the heavier-built Americans, unless they hit bone, caused no more damage than a 22 caliber rimfire bullet."Fackler, ML: "Literature Review". Wound Ballistics Review; 5(2):40, Fall 2001
Unfortunately I don't have online access to either the Wound Ballistics Review or the Journal of Trauma (Dr Fackler wrote in both and produced some of the first work on the 5.45x39 Soviet as well), but I was able to find what I was looking for here:
M4 "Loses" Dust-test - Page 12 - M4Carbine.net Forums see post #231. Back when I was in grad school I used to spend some of my down time reading Dr Fackler's articles in the Journal of Trauma. He's the real deal.
That comment about the 5.56x45 often producing wounds indistinguishable from a .22LR when the bullet path is short (as with an extremity hit or in the case of a very lightly built opponent), was from a man who has treated many many bullet wounds over a long career in the military. Ironically, when I made the observation that the 5.56's wounding idiosyncrasies could have been causative of the multiple hits at Sandy Hook (victims were reportedly shot between 3 and 11 times each) our resident commie over in the gun rights forum gave me s*** over it. Not like that bozo knows anything about wound ballistics, but our free socialist worker sure does know how to be a condescending a******....
*ahem*
Anyway, I didn't want to hijack the thread and start another "5.56 sucks vs 5.56 rules" thread, but I just get really irritated when I see some jackass on TV going on about the thing like its "Thor's Hammer" as you so aptly put it. If the gun grabbers ever manage to ban 5.56 rifles from US civilian service it will be a very dark day indeed, since next up will be all other rifles of greater power and lethality. And that's damn' near all of 'em.
The practical upshot of this for all those of us who use the 5.56x45 (I do, and if I thought it was useless I wouldn't have over 6,000 rounds of 'em in my stockpile) is that we have to be very careful with shot placement. Slovenly marksmanship that produces peripheral hits appears unlikely to be effective against an armed and aggressive opponent. But as the Marines have amply demonstrated in the sand box, head shots work just fine. That's one of the places where selection of equipment (good 1-4x designated marksman optic) and doctrine (aim for vital organs in the enemy not just center of mass on the popup targets and train to use 2-3 shots per opponent) comes into play. Or get a .308 and be happy that it will produce better stops reliably, particularly if you feed it with a 150gr JSP loading. By a curious coincidence that is exactly the loading in my M1A right now.....
Best,
Grumpy
PS Here's a link to the Emergency War Surgery book referred to above, albeit a later revision.
http://modernsurvivalonline.com/Files/medical/NATO-emergency-war-surgery.pdf The description of wounding mechanisms and profiles starting in Chapter 2 are very illustrative and worth a look.