To Create copy of movement journal entry by code in axapta you can try following code hint and can apply in loop also to create large number of entries.
InventJournalCopy _InventJournalCopy = InventJournalCopy::construct();
_InventJournalCopy.getLast();
_InventJournalCopy.parmJournalIdFrom('JournaNum');
_InventJournalCopy.run();