If it is not necessary to do it in VBA code, you can go to the page setup on the report and set specfic printer there and it will save with the report.
If you need to do it in VBA, you will need to open the report in preview mode. Then the following command may work; but I haven’t tried it. (Note: Reports(0) is the current report that is being previewed)
reports(0).Printer.devicename = “My Printer”