Looping a MC then Stop action

My file size was tiny then I added an animation of a worm jumping from one end to the other over 50frames!!! - the worm was drawn in Flash

and the size went huge…is there anyway of looping a movieclip approx 20times and then applying a stop action to it after the loop?

if there is can anybody show me how its done as I’m sure that would help me out?

cheers

Dips