Way back when I used to get ring waxed wads from the old Alcan company. They were indeed waxed only on the edges. I believe they were waxed by a process which slowly rolled them through a shallow layer of molten wax. The wax was of course only needed where the wad contacted the bore & the Ring Waxing saved a considerable amount of weight over those totally saturated with wax.

Miller/TN
I Didn't Say Everything I Said, Yogi Berra