That sucks.
I reload mixed brass as well on the 9mm. I have a problem with one particular brand....I can't remember but, it has a 10 embossed on it. It's not 10mm brass. I can't decapped the suckers, actually broke my decapper pin. Then I took a closer look and noticed that the primer pocket had some type of crimp around it, I guess they are crimping the new primer in its pocket. They dang sure don't want to come out. One thing I have learned, the least little resistance, stop and check it out. I guess that's the price we pay for using mixed brass.
Dadgum powder is still hard to find