My son bought me some self-defense ammo. Wicked looking round:

The Federal "Hydra-Shok", JHP, 230 grains, gives the most stopping power in the potent .45 ACP caliber. Another excellent load from Federal is the JHP, 185 grains. This round is well suited to a compact, short-barreled .45 pistol like the Colt Officer's ACP or the S & W 4516. It has lighter recoil than the Federal "Hydra-Shok", 230 grain, or CCI/Speer "Lawman", 200 grain bullets. Because of its higher velocity, the Federal JHP, 185 grains, is more likely to expand out of a short 3.5-inch barrel.

The Hydra-Shok bullet itself is copper jacketed, and very intimidating from the front, with the gaping mouth of the hollow point, and the 'Shok's most distinctive feature, the small rod inside of it that is designed to help the bullet expand by forcing any soft tissue encountered out against the edges of the bullet.

.45 ACP Caliber:
One Shot Stopping Success: 63-94% (Actual)
Self Defense Rating: Best
Recommended Cartridges:
Federal "Hydra-Shok" JHP 230 grains 94%
Remington "Gold Sabre" JHPP 230 grains 93%
Cor-BonJHP 185 grains 92%
Remington +P JHPP 185 grains 91%
CCI/Speer "Lawman" JHP 200 grains 88%
Federal JHP 185 grains 87%

http://en.wikipedia.org/wiki/Hydrashok