I have been reloading with 500 of your .41 Magnum cases for several years and I am only now beginning to toss a few cases with loosened primer pockets. I have actually lost track, but I know I have loaded all of them at least 10 times now. They still re-size without problem and I have never had a thinned out case wall. Eventually, I will replace them because I just want some new shiny brass, but they have held up better than any other handgun brass that I have used in my lifetime. Great product.