Diagnosis??

Thin walled brass with lead bullets might be the problem. The brass mentioned has always had jacketed or plated bullets in it. At least those I have seen. Never aead bullet.

I too have had good luck with PPU brass in my semi-auto handloads. The only roblem: was once years ago I had some 38 Special brass with primer pockets not being chamfered. Sharp, square corners. Nuttin' since...

FWIW, My experience is that PPU rifle brass is excellent. I prefer over almost all others. I do not know if their handgun brass shares this excellence. I have had only limited experience with their handgun brass unlike my experience with their rifle brass. Best wishes