One potential cause for this is that your Business Inkjet 5800 just lacks the physical capability to print on areas which are very close to the media border. Maybe it can be set to print with more narrow margins? Just check the printer manual...
Last, your printer driver/filtering system could be using a 'PPD' file which has defined margins that are too wide. That would set the logical limits of your printqueue for the border widths.
Check the following PPD:
Open this PPD with a text editor and search for the
ImageableArea keyword. It may contain a line saying:
*ImageableArea Letter/Letter 8.5x11in: "18 14 594 778"
It tells CUPS to set for Letter-sized...
- ...the left border to 18 Points,
- ...the bottom border to 14 Points,
- ...the right border to 612-594=18 Points,
- ...the top border to 792-778=14 Points.
(72 Points == 1 Inch).
You could edit that line to achieve a narrower border:
*ImageableArea Letter/Letter 8.5x11in: "6 6 606 786"
*ImageableArea Letter/Letter 8.5x11in: "0 0 612 792"
Follow an analogous procedure for every medium size you want to change the margin size for.
Caveats: If you set the logical limits to a more narrow value than the physical capabilities of your print device, it will not work. Also, it could lead to an increased toner/ink contamination of your paper borders and/or of your print device itself....