Start at the 8:00 minute mark of that same video.
"...however at the same time you launch that little bitty 55 grain pill coming out of an AR-15 at two and a half times the speed of sound, and it hits, and you see that radical planar tearing where you have tissue damage 5....6...inches away from the path of the bullet.  That's what creates that rapid hemorrhage, the blood pressure drop, the shock setting in, tissue disruption...hopefully in the right location...uh...cardiopulmonary collapse, and things cease, lights go out. "

Take that quote, and compare it exactly to what Fackler stated:



High velocity (above stretch/tearing speed) itself does not equal massive tissue damage.  That does not mean that there there is not an elastic limit to tissue (there is, and it varies).

Is just means that high velocity (in terms of stretch/tearing) is a force multiplier that works in conjunction with a primary wounding mechanism such as fragmentation or expansion, or even tumbling/yawing.

I mean, if we're just going to repost links, here's the 7n6 study again where it was shown that bullets traveling at 2900 FPS did practically no damage besides crushing effects in many elastic tissues.

https://web.archive.org/web/20090219104944/http://ammo.ar15.com/project/Fackler_Articles/ak74_wounding_potential.pdf

I don't know why you're so hung up on that one video, especially when the chief researchers who actually come up with this kind of theory have said otherwise. Again, ammo manufacturers are not wound ballistics scientists, hence why we see dumb shit like Hornady promoting 6-10 inches of penetration as "ideal" for home defense.

I don't necessarily think the guy in the video is wrong, I just think he only tells half the story. Maybe he didn't think it necessary to mention the need for upset since all rifle (spitzer) bullets do upset..eventually. The problem is that the longer the neck, the less total damage it does. And in thin targets, or at odd angles, it may even yaw too late.

I also think the 2,200fps mentioned is probably a good base number needed for a small caliber like a 5.56 to cause damage outside the crushing path. But I think that number can be lower with larger projectiles.
The picture of the 300blk exit wound in the hog posted earlier in this thread is proof of that.

I'm not "poo poohing" the video. I just find it strange how that one video can influence someone so much, especially after being presented written articles by well known ballistics experts and actual pictures that show that his argument is simply not true.

Hi Leid, do you know how large that exit wound was for the 2014 FPS Tac-TX? Looks approximately 1.5" in diameter.

That exit wound was close to 2" wide. The 110GR. TAC-TX bullets have earned their reputation for top-shelf 300BLK terminal performance.

I agree,
I think what he said was at a very high, very general level.  I think it was conflated with something different, taken out of context, and repeated as gospel.

I'd break it down into three areas:
1.  Is there a speed in which a projectile can exceed the elasticity of human tissue?   That is a physiological question with limited variables such as the tissue itself (fat? muscle? soft organs? lungs? blood vessels? health of tissue, including being weakened from fragmentation).   Someone may give a general answer of "x" fps, to cover many of the variables.   Bone would be an easier example to understand.  It either breaks or it does not.   What that particular fps does not state is the extent of damage.  (Similar to bone, it is either broken or not broken.  If it IS broken, is it a hairline crack? clean break? , compound fracture? Is it shattered with bone fragments causing more damage?).  "Stretch" damage that is only 1/4th a MM away from the wound isn't really a big deal.  Which leads to #2

2. I think the extent of damage is where all the other factors come into play.  Such as caliber, bullet shape, bullet construction, velocity, weight, angle of entry, etc.  How does that bullet react when it impacts?  There are tons of variables here.  You can be above "x" speed and do very little damage, or below "x" speed and do massive damage.  2200fps might be a general number where you exceed elasticity for 5.56, but all the other factors come into play in terms of extent.  There are so many factors, that is just gets glossed over. Which leads to #3.

3. Somehow 55gr 5.56 FMJ traveling at +2800fps, impacting, turning 90 degrees, and exploding (maximum extent of damage from fragmentation) has been conflated with "rifle damage", which has also been conflated with tissue elasticity of "x" fps.   So what we are left with is: 2200 fps = "devastating rifle damage", which isn't true at all, and ignores all the factors of #2.  
 

I honestly never thought that an intermediate monolithic bullet could make a 2” exit wound. I’m guessing it hit bone?

Correct. That raking shot impacted rib bones on the way into & on the way out of the vital organs inside the chest cavity. The expanded TAC-TX bullet had enough energy left to virtually remove approx. 2" of bone and the surrounding intercostal muscle tissue as it exited.

A .223 bullet traveling point forward won't do even a single millimeter's worth of temporary cavitation damage in most tissues. Note the 5.45 study where even the 7n6 bullets that yawed did not create wounds larger than themselves, except in the inflexible liver.

Drag, which is primarily responsible for temporary cavitation, is some combination of frontal area*instantaneous velocity*projectile shape coefficient. I am not sure what the exact value of each variable is since this may vary by medium, but it is likely that these are the main factors that contribute to the effect.

What this means is that a needle traveling point forward at 5000 FPS will probably do less temporary cavitation damage than a handgun JHP, i.e. pretty much none in elastic organs.

As for the general velocity range where most 5.56 SP/JHP starts causing damage, it is almost certainly much lower than 2200 FPS for the more destructive fragmenting rounds (e.g. 77 gr TMK) and likely lower even for bonded JSPs. Consider that Dr. Roberts has said .357 JSPs, which usually expand around 0.55 inches wide, tend to start causing damage at only 1600 FPS. 5.56 bullets are much less massive but often attain relatively greater expansion compared to their starting diameter - they usually end up somewhere around 0.45" above 2000 FPS.