Truth About Guns has a report on a new type of self-defense ammunition. I’m not convinced it’s going to work out all that well in the field, just because the logic of it doesn’t work for me. I’ve heard what generally stops a gunfight is being able to land hits that shatter bone and penetrate vital organs and tissues. This is hard enough for pistol rounds to do reliably when they are a single, large mass.
Think about an extreme example of this being bird shot. You’d be far better off shooting someone with a slug than with bird shot. You’re probably better off with the bullet staying in tact too. You don’t want to shoot through the target, but there are probably better ways to solve that problem than breaking up the projectile.