It was CCI's Small Rifle Magnum primer (CCI-450?), WC680, and a 212gr boolit out of a Lyman mold that DJ sent me to play with. The primers didn't help Hornady's 180gr Interlock tho, they still throw buckshot-like patterns. I am going to load up some other boolits that Bob gave me for comparison and see if it does the same thing with them.
Ian