In my experience, cartridge cases are nearly always to blame for many of the problems I have experienced in more than fifty years of reloading. I have had brass that was too soft and flowed into the ejector, in the starting load. I have had primer pockets expand and become unserviceable after initial firing. However, I have also experienced brass that was too hard and brittle, that split on the first firing. I have had factory ammo that came from the factory with split cases. I have also loaded and fired cases nearly thirty times before experiencing any failures. These things vary from lot to lot and there is no easy remedy, especially in the current environment, when you essentially take what you stumble onto, in the way of components. This even applies to nickel casings, I have discarded nickel casings because the plating was peeling and they looked hideous, they had been loaded numerous times but did not split. Starline has been consistent quality, in my opinion, perhaps more than the major manufacturers.