Setting particle emission at random keyframes? I'm  creating a physical simulation of apples falling into a box using the bullet particle system and Copy Particles to Rigid Bodies code by liero. However, the apples always fall in equal frame intervals according to the selected number of particles, frame start and end. is there any way to randomize the frame intervals? 

Thanks
I don't think you can do it with particles. Can you place your apples in the tree (with rigid body > active + dynamic disabled) and animate the "disabled" properties in the timeline to choose what apple start to fall?