Blinddog, and others...
I was the Department "Armorer", Range Officer and "resident Mad Scientist"...
We did extensive testing of almost every conceivable factory handgun load in .38SPL, .357, 9mm and .45ACP (and a lot of others) that existed over a ten year period to be ready to advise deputies as to what loads to carry (and what loads we wanted them to carry).
One result was that we almost universally rejected any handgun "hollow point" because of the unreliability factor for "expansion". The lighter loads in JHP failed to expand many times. Especially in simulated "Fall/Winter" situations... a t-shirt, flnnel shirt/sweater, and insulated jacket placed over ballistic gelatin; produced unsatisfactory penetration and NO EXPANSION most of the time. The nose cavity of the bullet either filled with material like a paper punch or simply sheared off.. especially at any angle other than 90 degrees of impact. In the end, we found that in .38SPL, .38SPL +P (and +P+), and .357 and 9mm (a woefully inadequate defensive round in my opinion after all the testing because of low bullet weight), and .40 and .45... the best bullets were flat nosed and of those the SWC was the best. These relied on penetration for effectiveness and transfer of energy (and frankly doing the most trauma).
The "scholarly" and anecdotal information that I have gathered and digested seems to support this opinion.
Now, I don't want to start WWIII (or any kind of argument), but it became my opinion that in handguns there was 1) no substitute for caliber, and 2) neither the light, fast (100-135 gr) or real heavy slow (185-200gr) .38(or 9mm or .357) bullets excelled over the 140-160gr offerings. Same in the .45.. the 200-230gr seemed to be the most effective.
Our worst nightmare was lived out by a friend who placed six Winchester silver tips from a 9mm into a perp (traffic stop) only to have him still standing and effectively use his .38 snub nose to score three hits. (Stopped him with his .25 backup as he stood over him reloading..direct hit through the underside of the jaw...
I used a hardcast (wheelweight lead) 220gr SWC in my .45ACP (1911), twice. Both times were instantaneous "stops".