Disbelief

A likely story
Balderdash
Baloney
Bull
Bunk
Come off of it
Don’t make me laugh
Fiddle-faddle
Get serious
Go on with you
Hog wash
Hokum
Horse feathers

I bet
In a pig’s eye
My eye
Nonsense
Pshaw
Rubbish
Says you
Tell me another one
That’s a laugh
That’s a lot of hooey
Tommyrot
You’re dreaming
You’re putting me on