If you want to keep only specific columns from each record, you can do that with DFSORT's INREC, OUTREC or OUTFIL statement. For example, if your input file has RECFM=FB and LRECL=80, and you want to keep only columns 11-80, you can use these DFSORT statements:
OPTION COPY
INREC BUILD=(11,70)
If you're not familiar with DFSORT and DFSORT's ICETOOL, I'd suggest reading through "z/OS DFSORT: Getting Started". It's an excellent tutorial, with lots of examples, that will show you how to use DFSORT, DFSORT's ICETOOL and DFSORT Symbols. You can access it online, along with all of the other DFSORT books, from:
http://www.ibm.com/servers/storage/supp ... tmpub.html