I know this is an old thread, but I found it while searching for a solution to SDB priming problems that often resulted in unusable ammunition. It was becoming very frustrating, as I have been using a pair of SDB’s for over 30(?) years. I went into my XL-650 parts drawer, and located a small primer sized magazine with brass tip, and compared it to the SDB, and it looked the same, except for the brass tip. I went ahead and installed it, and proceeded to crank out 100 rounds of .38 Special ammunition with -ZERO- problems!!!! I will be ordering two for each SDB, large and small.
thank you for the help!