I remember in the old days all we got were Remington caps. Or those crappy corrosive Dixie Gun Works Italian caps in the little plastic container. I remember the first CCI’s we got in at the shop. There were some ignition issues with the CCI’s then. They seemed then, no hotter than the Remingtons. Then the RWS caps started gaining popularity. You could pop a Rem or CCI, okay. Then pop an RWS and it would almost ring your ears.
I’m talking 40-50 year ago stuff. We sold the hell outta RWS caps. Instead of foil liked like the Remingtons they were laquered on the inside. I believe the CCI’s were laquered too. Happy tonhear CCI’s are hotter and less problematic now.
Digging through my dad's stuff after he passed I found approximately 2000 of those old Dixie caps. IIRC they're hot but very corrosive.