Time from Pip to hatch?

[jamesrm]

I have 200 Bob White eggs (my first batch) that are due to hatch today. Using a GQF Cabinet Incubator, all eggs are in the hatching tray. I recieved my Hatcher the day after I had to move the eggs, so I have it up and running. I am planning on moving birds over to it as they hatch, in batches a few hours appart to give other eggs room to open up.

How long should it take the birds to come out of the shell after they are pipped? Is there a time period I should open the shell if they do not do it on their own?

Thanks,
James