It may "still be fireable", but I (for one) wouldn't fire anything off in a gun made with metal that old, unless I had an excellent, fully-paid health coverage; wore armored gloves & facemask - and even then, only with special, low-powered ammo from the likes of PolyWad, RST, etc.
Certainly not with any modern ammo, even "low brass" .
I value my eyes & hands - a LOT !
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