Abstract: A bullet is formed with a hollow interior compartment which contains particles. The bullet side-wall surrounding the hollow interior compartment breaks after impact with the target to release the particles from the hollow interior compartment. Preferably, each particle in the hollow interior compartment has a core substance and a coating surrounding the core substance. The coating is designed to release the core substance after the bullet contacts a target. The core substance swells when in contact with blood, which may be time delayed in order to enter the blood stream.