I dug a hole in back yard to bury a pet and was down deep enough 3feet and was into clay. No not hard work I have a lil tractor with a loader. So a little Google work and I made some wild clay. It was made into a slurry then strained through window screen material. Slurry left to settle out some water. Poured slurry into cloth over a 5gallon pail then tied into a ball of muck. A few days later poof have clay. As a shooting media it's kind of fun. I made this clay to test slugs made from Corbin setup....that I haven't gotten yet. But couldn't resist a few shots with 59gr zan at 960fps. Started with 5X5X8 blocks will need to make prolly 10x10x15 for actual testing. Here are a few teaser clips for fun