Chris I use a milk carton over the powder then a 1/8" lube wad a .052" hard wad cut from NAPA Karropak gasket stock over the lube wad then a 1/16" cork cut from dense gasket stock from Tractor Supply Co. and a .012 poster card stock.
This stack holds the gases back very good and it shows on the ES.
This may look like a lot of wads but it fits nicely in the .44 bottle necks.
I tried doing away with the lube wads but I get excessive case stretching even separation.
I have always used cork cut from 1/16" or even 1/8" Cork wads are nothing new the ODG's also used it so there must have been a reason
Kurt