I know the Germans fielded non-corrosive primers in WWI. They had a very short life span and had to be used within 12 months. In WWII many Germanicon rounds were NC. The US Army could have easily fielded NC ammunition in WWII but elected to stay with the FA-70 Corrosive primer. The Rifle Bore Cleaner the US Army issued was excellent for cleaning but had a very obvious smell. It was so obvious the in Viet Nam the US Army issued a new family of cleaning solvents that were odorless.