"Initially, the plant was known as the Twin Cities Ordnance Plant but it was renamed the Twin Cities Arsenal in 1946 and finally, in 1963, the Twin Cities Army Ammunition Plant."
"In 1965, during the Vietnam War, the plant was re-opened for the manufacture of new types of small arms ammunition. It was on standby status from 1976 through 2002."
Treat the same as Lake City. Regarding the age, yes 1972. There is still quite a bit of Vietnam era age brass around. I use it without hesitation after inspecting for obvious flaws.