zakrawacz
The movie file is recorded in 30 fpses but the actual movie gets serious fps hit whenever:
but there is a scene in the movie that was shot in 5fps (huge action scenes)you really need to provide some sample video here
we can watch it together, frame by frame
In this tutorial I`ve found there is an example of movie being encoded in 60fpses (like decoded to raw and then encoded again and saved as new file with 60fps all the time).
http://www.spirton.com/convert-videos-to-60fps/
Other than that - I don`t have the device in my home to record in 60fpses so can`t give you example made by me.
http://mckack.tumblr.com/post/3535190601/60fps-vs-24fps
another example of stable 60fps (a classic) - to see this you need to click the link below the youtube and download the 23mb .avi.