Oops. I guess I should have checked the post right above mine.
This led me to wonder if he had a gun. I just found this posted this morning at CNN. It's Steve Belford telling how Rader killed his mother, Shirley Vian:
The man then went to a neighbor's house and Relford went home. A few minutes later, there was a knock at the door, and Relford raced his brother to answer it. Relford opened the door.
Once inside, the man "immediately starts pulling blinds, turns off the TV, reaches in his shoulder holster and pulls out a pistol," Relford said. http://edition.cnn.com/2005/LAW/02/28/btk.relford/index.html
If you run across any news on a pistol that Relford had, please let me know. If it's a .22, then you can bet the LE are doing ballistic tests as we speak.