Uhmm... don't you mean boxer primers have that reputation, considering most all commie military ammo and commercial combloc ammo is....berdan primed
No, I suspect Boris is talking about popped primers in new production steel cased Berdan stuff that seems to give everyone the worst headaches. You never heard about popped primers with 70's Chinese surplus or Yugo M67 (or original Russian M43 for that matter), but the past 15 years to current production Wolf, Tulammo, Red Army Standard, and even Golden Tiger and the Bear flavors to some extent have many documented issues. Of course, they are all contracted to four or five ammo plants and production shifts around every once in a while, so there may be a common denominator there Maybe the primer alloy is too brittle, or it's too thin, or the energetic inside the primer cup is more powerful?
I do know the Murray's 'neck and throat' procedure allows a bit more room before the bullet contacts the lands, so it appears internal pressure or perhaps the pressure change rate has something to do with it. I also know that the Sino-banian I had major popped primer issues with resolved itself when I took a stone to the end of the FP and rounded it off a bit as it was very square with a flat face and sharp corner.
It's one of those mysterious issues that come along and bite you in specific guns once in a while.