Uncheck "fit to size" or make sure the scale is at 100% before you print. If you are printing right from your web browser, here are some shortcuts for finding this setting. Once your printer dialog box pops, do the following steps:
Chrome: Click "more settings" and change scale to 100%
Safari: Next to "orientiation" is "scale", set to 100%
Firefox: Click "show details". Next to "orientation" is "scale", set to 100%
Internet Explorer: Under "page sizling and handling" is "custom scale', set to 100%