diff --git a/qpms/vswf.c b/qpms/vswf.c
index 37e728a..1d0e349 100644
--- a/qpms/vswf.c
+++ b/qpms/vswf.c
@@ -131,7 +131,7 @@ size_t *qpms_vswf_set_reindex(const qpms_vswf_set_spec_t *small, const qpms_vswf
     while(big_pairs[bi].ui < small_pairs[si].ui) 
       ++bi;
     if(big_pairs[bi].ui == small_pairs[si].ui)
-      r[small_pairs[si].i_orig] = big_pairs[si].i_orig;
+      r[small_pairs[si].i_orig] = big_pairs[bi].i_orig;
     else
       r[small_pairs[si].i_orig] = ~(size_t)0;
   }