Hello forum i need help

I designed my report using a user defined paper named "Voucher" ( width 8.5 inch,length 5.5 inch)
but When i print directly to the printer from my web the result is not using voucher paper but Letter.
I search in the internet and i found and article that suggest to use this code
oReportDocument.PrintOptions.PaperSize = CType(133, CrystalDecisions.shared.PaperSize)
I allready add that code but still failed but the size allmost correct i predict it print on the most similar paper A5 rotated ( width 8.27 inch, Height 5.83 inch )

can any one help me to defind the code correctly to make the report printed in the correct paper size

Please give me a solution
thank u in advace