Left 4 Dead 2 Facts #26 - Pipebomb vs Specials
All throwables can stop a Jockey/Hunter from reaching you and destroy Tank rocks. However, only the Pipebomb can stop a charging Charger. All throwables, while in the air, is considered "solid" and will get in the way of whatever is coming towards you. Only the Pipebomb stays solid on the ground, meaning if a Charger runs into it he will stumble.
All throwables can stop a Jockey/Hunter from reaching you and destroy Tank rocks. However, only the Pipebomb can stop a charging Charger. All throwables, while in the air, is considered "solid" and will get in the way of whatever is coming towards you. Only the Pipebomb stays solid on the ground, meaning if a Charger runs into it he will stumble.