I thought I had seen / read about some catastrophic failures using LiL Gun and cast bullets ...
No, you may have read about the POS Winchester large rifle primers in the 500 S&W, I had one pierce and spray campfire member Rockchucker with shrapnel, it was a medium load with the 440gr Cast Performance bullet at 1350 fps.
I went home and had to pull damn near 400 rounds, shltcanned the wlr's forever, reloaded with CCI-250 magnum primers, not one single solitary problem since, that includes the hellbender load with the same 440gr hard cast at 1600 fps, that one bucks a little.