I think that a good deal of the research into the wounding effects of handgun bullets has been taken out of context for such a long time that many people have lost the initial point. What one must first understand is that all firearms, be they handgun, rifle, or shotgun, cause trauma to living things in one of two ways: either they directly crush/tear tissue (permanent crush cavity) or transfer their energy to such a degree that it stretches the tissue beyond its elastic limit (temporary cavitation). The notion that there is some magic velocity at which one crosses the threshold from pistol to rifle performance is erroneous because for just about every figure I've seen thrown around as the "magic number" I can point to a very effective rifle cartridge with lower velocity or a pistol cartridge with higher velocity that still behaves like a pistol.
The reason, instead, that rifle cartridges are typically more effective is that they generally produce more energy, be it with higher velocity or heavier bullets, which in turn makes them more likely to produce temporary cavitation beyond the elastic limits of most tissue. Also, rifle bullets, due to their typically higher velocity and the difference in the feeding mechanisms of rifles as opposed to handguns, can often be constructed to expand and/or fragment in ways that cannot be duplicated with most handgun bullets.
For example, even a FMJ rifle bullet like that of a "battle rifle" class cartridge like .30-06, 7.62x51, .303 British, 7.62x54R, or 7.92x57 Mauser can be made to destabilize and create a very large temporary cavity while still penetrating very deeply. FMJ handgun bullets, on the other hand, typically just drill right through retaining most of their energy and creating a rather modest amount of temporary cavitation.
Likewise, by using a JHP or JSP bullet or even by just driving the bullet at higher velocity, rifle bullets can be made to fragment at a sufficient depth to cause devastating effects on living things. By comparison, while handgun bullets can be made to fragment, they typically require bullets so light and/or fragile that their penetration is reduced to unacceptable levels. This is why, in most cases, fragmentation is considered undesirable in handgun bullets.
Now, most agree that the best type of bullet for most handgun cartridges is a hollowpoint of one sort or another. These reduce (though not eliminate) the risk of overpenetration to bystanders, increase the frontal area of the bullet thus increasing permanent crush cavity, and increase the temporary cavitation to the degree that it might increase terminal effect in some of the more inelastic tissues of the body. The problem is that most handgun cartridges simply cannot produce the violent expansion/fragmentation of rifle cartridges without sacrificing adequate penetration.
That is not to say, however, that there are no handgun cartridges that can produce rifle-like terminal effect, there certainly are. The reason, however, that such cartridges aren't more commonly used is that they produce recoil beyond what LE and military organizations (the main drivers behind research into handgun effectiveness) feel is acceptable and/or they aren't commonly found in the type of handgun that such users want. I refer to these cartridges as "magnum-class" and the least powerful common cartridges that fit this category are .357 Magnum and 10mm Auto. These rounds have enough raw power to drive a bullet heavy enough to penetrate adequately fast enough to fragment moderately (usually core-jacket separation). Of course, going up to cartridges like .41 Magnum and .44 Magnum can also give similar results with the right bullet, but the recoil will be increased as well.
Of course, most LE and military organizations have little or no interest in these cartridges. The FBI tests are a prime example of this: the FBI had no interest whatsoever in revolvers as they'd already decided that they needed/wanted a semi-automatic handgun and the 10mm was deemed to have excessive recoil unless it was downloaded to the point that it behaved no differently than any other common "service-class" handgun cartridge.