FWIW & some of this you may already know. I loaded Wonder Wads in Browning B-78 .45-2.1 (AKA .45-70) several years ago. I have not tried Wonder Wads in any other BPCR or caliber in my BPCR" travels" .
Generally speaking, the purpose of the wad is to protect the base of the bullet from gas blow-by w/ the resulting leading of the bore & prevent lube migration into the powder column.
Since the Wonder Wad is dry lubed, I dont think that you need to be concerned w/ lube migration unless you are utilizing a very low melt lube & leave your ammunition in the sun. If this is the case; you probably would need an additional wad to keep the lube from the powder.
But why add another step to the reloading process-- the "rough & rugged road" of BPCR reloading is long enough. Better yet change the lube as you could starve the bullet for lube , w/ leading & hard fouling as results
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The Wonder Wad will protect the base of bullet; however, you do need to prevent any wad from adhering to the base of the bullet upon exiting the muzzle. If the wad stays on the bullet, there is very good chance that your rifles accuracy will suffer.
When I loaded the Wonder Wad (or any other wad for that matter) , I wipe the base of the bullet on the ubiquitous Post It Pad to remove any excess lube that possibly could hold the wad to the bullet.