I've been told that in these smaller calibers the truncated type bullet is the most effective.
FMJ will penetrate, but might glance off bones and generally cause small wound channels. Also the idea of ball ammo simply "slipping through" one's body without doing much damage to anything other then what is exactly in front of it.
JHP might penetrate and give a large wound channel, but in calibers of .32 acp and below the penetration is really just not there.
A truncated bullet works like a FMJ, but instead of easily cutting a pathway through the flat tip seems to just bash it's way forward. Plus the sharp edges of the flat tip gives the bullet less of a chance to glance off bone.
Yes I know a gust of wind can stop a .25 acp (kidding
). Would a truncated bullet in .25 acp yield the best self-defense function then a FMJ or JHP?