What makes the Rifle rounds so much better at stopping someone than a Pistol round lets say a .45 acp Vr. a 223 remington the .45 has a biger slug to take out more flesh right. but the 223 could go right threw the person and not take out very much??
Don't know for a fact, haven't done an experiment on it, but have made the calculation back in my days in college (one of my profs was a shooter). Would have to dig it out (may try to) but when a bullet penetrates a membrane (skin, water jug side, etc.) it works a lot like an jet aspirator (i.e., it sucks air in behind it). The amount of air pulled in increases significantly if you maintain at or above sonic velocity after passing through the membrane (the entrance point is now an orifice). If the calculations hold true, you should see some pretty significant stretch cavities off of high velocity rifle rounds.
In other words, what Rosco said.
[This message has been edited by gm45 (edited 09-07-2001).]
Another factor is fragmentation. The .223 is particularly devestating if the velocity is still high at the point of impact. From what little I understand of it, if the velocity is still extremely high and the twist rate is high when the bullet impacts you get the tissue damage Rosco so eloquently mentioned and a fragmenting bullet which does further damage.....generates even more blood loss.
But, that all depends on bullet contruction, velocity, twist rate,,,,,yada,,,yada,,,yada.
A B.S'er I am, a ballistic scientist, I am not, so don't take everything as gospel.
"The other terminal ballistic effect is what happened to those milk jugs, now called 'Temporary Wound Cavity.' The shock wave that accompanies bullets causes a wild but temporary inflation of human tissue, lasting only a split second and having little incapacitating effect if the projectile is a slow moving pistol bullet...
...When it comes to temporary cavitation, the effects supposedly are not as predictable and therefore should not be considered, although it's known that temporary cavitation inflicts injury to nonexpanding tissue such as the liver, brain, and kidneys, as well as liquid-filled organs like the bladder. The least cavitation injury is to tissues that readily stretch, such as the lungs, muscles, skin, and ordinary blood vessels...
...But much of the current ballistic theory is based upon pistol bullets, although rifle bullets usually inflict much more damage and possess five or even ten times the kinetic energy."
Maj. Plaster also discusses in this book the in's and out's of using .223 as opposed to .308. Bottom line: hollow points or fragmentary rounds can cause much more damage than FMJ.