Very Old Packets (1950s-60s) Steel case, Berdan, Very Corrosive Primers. Commercial ( so called) Production for sales into Eastern Bloc Nations and Others as "Sporting ammo" ( sic).
Interarms ( Sam Cummings) brought a lot in via Finland and the Czech Monopoly "Omnipol".
If there are only a few Packets, an interesting Collectible Note on the History of US "Arms Dealers/Importers" and a different Facet of the Cold War.
As I said "Very Corrosive" so the Usual Advices apply. Also, at this age, the Primers may be cactus as well...Be warned.
Doc AV