So I roll crimp all my rounds, especially slugs. I don't use commercial plastic overshot cards because they are so frangible. They are made to be, I know, but if I drop a shell the OS Card often breaks leaving the round ruined.
That leaves me with cardboard OS cards. They work great, but are susceptible to water. Not great for hunting trips if it rains.
So, any thoughts on waterproofing cardboard OS cards that wouldn't effect the round? Maybe spraying Thompsons on it, or some other sealant? Maybe paraffin wax? What do yall think?