Video: Handgun Ammo & Wound Ballistics
One of the best, simplest, to-the-point videos on defensive ammo as it it pertains to wound ballistics I've seen.  Watch it.  It's from Lucky Gunners and includes interviews with two of Federal/Speer/CCI's top dogs in the ammo testing an development area, guys that have worked with the FBI closely on this and understand handgun wound ballistics.