What is a hollow point pellet and when do I use it?

A hollow point has a cup or cavity in the head designed to expand on impact, dumping more energy into soft tissue and limiting over-penetration.

They work best at short range from medium- to high-powered airguns; expansion typically requires impact velocities around or above 600 to 800 fps depending on design. They are a hunting pellet for squirrel- and bird-sized game inside about 30 yards. At long range or low velocity, the hollow point does not expand and the cavity actually hurts the ballistic coefficient.