Some of the ol' timers might remember the wax gas checks that were sold quite a few years ago, I think the guy who made and sold those is still around but hard to get in contact with these days.

Anyhow, I am wondering what he used in his gas check material that made it special or different from plain old dental wax?

I had some 340gr SSK boolits loaded over 22gr of WW296, these loads were put up in 1995 or thereabouts, and I had forgotten about using the wax gas checks, and I shot them and noticed this red ring of waxy stuff on the case mouth and I thought wtf is that? Wasn't until a few weeks later that I realized those had been loaded with the wax gas check sheets. They still shot well, were accurate, and you could clean the barrel with not much more than a wadded up paper towel.

Maybe it was a passing fad back then, and maybe they didn't work quite as well as the maker claimed but I had fairly good luck with them when I started using them and would like to try them again. It's likely they didn't hurt anything, and could serve to "season" the bore somewhat between shots. I have some .060" dental wax sheets that I will probably use but I am wondering what the dental wax might be missing.