I have read alot of threads on here about natural hog casings being tough but can't find what I'm looking for on here or the Internet. So if I could get some help it would be greatly appreciated. I bought a hog hank and made some bratwurst and the casings were excellent, I put some water to cover the casings I didn't use in a plastic container in the fridge with IODIZED salt since that was all I had. So the following week I made more bratwursts after rinsing the casings and when I finished stuffing I pricked holes in the casings to link them. I grilled them as I always do but I could bit through the whole casing or if I could it was very chewy and no good. I stuffed them as full as I could. Would the iodized salt do that? Can I bring them back around? Maybe I put to much water in the container? I hope I didn't ruin them. Oh and the casings were from curleys.