I first saw the story about a gun falling out of the pocket of a woman who was talking a walk near waverly. She sat down to tie her shoe laces when it fell out and the impact of hitting the ground caused the trigger to jerk, firing the weapon.
http://www.lincolnonlinenews.com/pages/14943713.php
Hm. You seem to have some data/information that isn't in that particular story. Particularly since the story says "at her home".
And I'd be curious to see what gun goes off without the trigger being pulled.
As far as 147gr FMJ's, I'd shoot heavier rounds IF I could find them (and afford them). It's about penetration power. If it is winter, or the perp is wearing heavy clothing or layers of leather (home made armor), or is even moderately obese and your bullet blows upon the surface, or shortly under it, it may never hit vital organs.
JHPs tend to react like FMJ if the opening is plugged---matter of fact, that is what denim tests are for (when they put denim layers over the gelatin). It isn't to see if the bullet stops (which it won't) it is to see if the JHP will still expand upon reaching the gelatin or instead act like a FMJ.
My question wasn't about 147s. It was about why FMJs instead of JHPs.
As far as heavier bullets hitting bystanders in the background, if you haven't taken that into consideration BEFORE you decide to shoot it doesn't matter which round you are using. In the excitement you could graze or miss the perp and hit someone standing behind him. And, I've investigated several shootings and homicides for law enforcement and basically people don't die from cavatation wounds caused by hand gun hollow points. They die by bleeding to death. The deeper the hole the more bleeding. Death is only instant when they are hit in the brain or brain stem. High velocity rife rounds are another matter. An HP round fired from a rifle will most definitely create a huge and lethal cavatation wound.
Actually, "the deeper the hole the more bleeding" isn't necessarily true, as research into JHPs has shown when compared to FMJs that punch all the way through. As many people in the military can attest, 9mm FMJ tends to punch little holes all the way through, and does not incapacitate quickly. It is certainly true that NO handgun round incapacitates quickly unless directly to the CNS. However, it is also true that JHP rounds do significantly more damage than FMJ, especially in smaller/faster bullets such as 9mm, and that if you don't hit the CNS, JHP will at least stop the attacker faster than FMJ.
I didn't mention cavitation, because you are correct, with handgun rounds there effectively isn't any worth speaking of, because the elastic effect is too minor, and the tissue just stretches.
None of this changes the fact that JHPs still are shown to be significantly more effective than FMJs, which is why no one but the military uses them.
BTW, did you know that it is against the Geneva convention to use HP rounds in warfare? And that the US Army recently ordered 4.5 million rounds of HP ammo. If they can't use it against the enemy then who is left? Citizens?
Someone else has already made the correction for this statement, so I'll leave it alone.
I still don't understand why FMJ instead of JHP (plenty of 147gr JHP out there---Ranger-T and Federal HST come immediately to mind), and the comments about the women shooting herself just seem odd to me, as you are saying things that weren't in the report, and it's a rare gun that "goes off by itself".