Well, there’s always first time for everything. Copped a face full of gas, as I was testing one of my old (when I say old, I mean OLD) 22 pumpies. Pssssssstttttt. Popped those safety glasses on quick smart!
Note the raptured case near the base.
Not a painful experience, not enough to crap myself, but certainly warranted a reasonably large shart.
Back on the bike! Eye pro on, rack, fire from the hip a few to make sure it’s just the one 
Safety squint’s are always on the ready… If somthing feels to sketchy its saftey glasses on lol…
Looking at the two pictures, without impugning the ammo you show, suggests that the firing pin has sheared through the entire rim and part of the case. That could not have happened if the cartridge was fully in battery. Nor could it have happened if the firing pin protrusion is correct.
I’d be having a very close look at the operation of the firing pin w.r.t. it’s correct retention and maximum protrusion from the bolt.
I’d say it’s most likely not the ammo. Ammo shot just fine after and in all other guns. So you’re probably correct.
I’ve only ever had it happen once, a tiny sting to the face for a second but the itchy eyes & ringing ears lasted until the next day. I’ll never use some dodgy bastards muddy old gun from behind the utes seat again.
