Convert RAW 1022 to XString

Hi,

i have got a PDF-File in a RAW 1022 table and want to convert it into a XString.

I tried to do with SCMS_TEXT_TO_XSTRING, i got a result but a wrong one. My table has 11 lines, so the xstring should have 11424 characters - but it has 15627... Can anyone help to solve this problem?

DATA: file_tab TYPE TABLE OF bapiconten,
      file_xstr TYPE xstring.

* [...] PDF into table [...]

CALL FUNCTION 'SCMS_TEXT_TO_XSTRING'
  IMPORTING
    BUFFER   = file_xstr
  TABLES
    TEXT_TAB = file_tab
.