for what it's worth when I bought my first 1911 of my own I think in the year 2003 I shot some of my dad's World War II steel case .45 ball ammo through it.
(Before I shopped four and ordered a good quantity of my own new commercial ammo.)
Headstamp said 1942 or 1943 production.
It was 100% reliable and quite powerful.
Shot 50 rounds of it some 60 years after it was produced.