Like BLUE RIDGE BRASS!! I get all my 40 cal (filthy considering that I possess the means and can easily clean it myself) cases from Blue Ridge Brass! I get it because of the 4,000 at a time and haven't had a 10mm scenario in the bunch, nor a 9mm wedged within one of the 40’s. They are doing a great task!The go-to preference of shooters, Precision