Please add the following line to your code. This line will make sure that the page isn't scaled when printed:
This is the only parameter you can set to influence the print setting.
You can't tell a viewer that it needs to fit the page to the size of the printer page.
You can only instruct the viewer that the actual size needs to be taken, by setting the
Click this link if you want to see how to answer this question in iText 5.