Yes, pretty much any kind of thin paper should work to seal off powder kernels and keep them where they are supposed to be and not affect pressure or wad column height. Wax paper might be the best choice in that napkin paper might smoulder being a bit "puffy". Not sure where you are but we are into fire season here and the bush has been very dry.
Please post results from your kinetic puller. I am wondering if PVC will be robust enoiugh to take the pounding. If the PVC a better way to go than what I did.
I used 3/4" steel pipe and that worked fine but I did have to whack a wood block pretty hard to get the crimp to open. Then again, I was breaking down slug loads. As you say, once the crimp is open a bit the shot will pour out then you can pull the wads out with needle nose pliers.
Longbow