Peter, Its almost like the proverbial how long is a piece of string question.
It depends totally on the aircraft type, what does it say in the POH for rudder checks? Thats always going to be be the standard point of reference.
If you look at some tail draggers, you can lift a the tail off the ground while doing your walk around and check the rudder is free from limit to limit. Others have castoring nose wheels, some have spring linked rudder pedals to nose wheel. It really does depend on the type of aircraft and what it says in the POH.