Scope cap for Bushnell 4200
What size Butler Creek scope caps does everyone use on a Bushnell 4200 6-24x50? My objective cap fits fine, but my eyepiece cap won't stay on. It's a size 14 that SWFA shipped it with the scope. Do I need a size smaller? Problem is I haven't seen any locally to test fit. Any tips or tricks for making it fit more snugly?