Particle doesn't trigger OnParticleCollision

For my project I use a particle system to emit projectiles. And although I have an enemy object with a script including OnParticleCollision that is supposed to destroy it, nothing happens when the particle hits the object. The projectiles go straight through the object although the object has a rigidbody and a collider. The collision for the particles is on, send collision messages is on. What am I doing wrong?