The reason I mentioned the fast hang fire issue is that this only seems to be occurring in semi auto firearms.
I have always put the fliers in my bolt rifles and mini 14 down to extremely hard primers in this ammo. On several trips to the range, I've picked up more than a few complete cartridges where the primers didn't ignite but were dimpled. The dimples weren't deep enough IMHO to ignite the priming compound.
I just looked at the cases in a small box where I keep them. They are all stamped CJ95.
All of my crates are yellow boxed CJ93. With a couple of hundred rounds of this stuff through a mini 14 and no issues such as the OP and several thousand rounds through 4 different bolt rifles, mine and others, we've never encountered the longitudinal splits in your pics.
The fact that they are longitudinal, rather than horizontal is telling you the cases are consistent and that you have high pressures occurring in those case at the instant of ejection. If it were a case failure, especially at the thick part of the side wall, just above the base web, the cuts would be horizontal ruptures rather than burnt through longitudinal slots.
If I had a couple of those, I would take a hacksaw or Dremel tool with a zip cut blade and cut one in half, from case mouth to base, without compromising the blow outs. That way you will be able to see whether they are actually burn throughs from pressure or ruptures.