Forgive my ignorance of things Glock. What was up with the water failure? Marine cups, I think he said? WTH?
Water can get in the firing pin channel.
It acts like a shock absorber and slows the firing pin. Causes misfire.
Marine cups allow slop, so the water can be displaced.
But, that opens the channel if you blow a case.
They are used in guns meant for users that might immerse them.
