First you do have to delete all your item records associated with that copy, then you can purge the copy record, serials checkin history and prediction patterns in one simple step. 

1. Send the title to Serials Control.

2. Highlight the copy to be deleted.

3. Click the dropdown Copies menu. 

4. Choose Purge Copy from that menu. The program will tell you that "this purge will remove associated data from these tables:" and cite tables like Olga, Holding Summary, Copy issue, Copy Issue Serial route etc. (Note: If the message appears but then no tables are cited, just cancel and do a File > Delete Record instead).

5. Click OK and the copy will be removed.