Lightroom :: Why 4x6 And 5x7 Prints Being Clipped

My prints are getting clipped no matter what I try to do.  I am losing approximately 1/8" from all sides of the finished print.  From what I can tell, the picture is actually printing larger than the specified size.
 
This is my process:
 
In the Develop module I am cropping to the desired aspect ratio using LR presets, then going straight to the print module.  My printer is an HP Photosmart C4780. In the Print module I set my margins to 0 and cell size to 4in x 6in.  The picture on the screeen looks exactly how I want it to print. I go to Page Setup, select my printer, paper size (borderless 4x6) and orientation, click OK. Then to Print Settings, select the HP paper I am using, click borderless, click save.  If I click "scale to fit paper size", I still lose approximately 1/16" on each side. Under Image Settings, I deselect zoom to fill.  I have tried selecting it but still experience clipping. I have tried moving the margins in by fractions of an inch and I seem to recover some of the image, but its a long trial and error process that I feel I shouldn't have to do.
 
A 4x6 test print on regular 8.5x11 paper measures 4-1/8" x 6-1/8".  The print layout in LR clearly says 4x6.