problem with fingers

Can someone explain this animation artefact which is shown in the video (Projectile FX doesn’t follow the bone properly)

It happens under these circumstances:

  1. Only certain paragon characters
  2. When camera is zoomed out
  3. FX is attached to a finger bone (in this particular case index_03_r) , the problem cannot be seen if FX is attached to a hand bone

It seems that’s it somehow connected with the size of the character on screen. See how it can be reproduced with a smaller character when i just resize the window: