Prewar and war time 27's have no date on them, the exception being those marked as being used by Nazi police forces. Those will have a date along with 'Eagle K' on the trigger guard. Post war 27's will be date marked. Mine run from 45 to 48.
CZ22, CZ24, CZ27, CZ28, CZ36, CZ38, CZ45, CZ46, CZ50, CZ52, CZ75, CZ82, CZ83, CZ85, DUO, Mars, Z, M1922, Praga, Praha, Slavia, Little Tom, VZ24, VZ33, VZ52, VZ52/57, VZ527, VZ54, VZ58, VZ98/22, ZKM451, ZKM455S