In 1942, on the recommendation of the Council for Scientific and Industrial Research (from 1949 Commonwealth Scientific and Industrial Research Organisation, or CSIRO), McTaggart was made its employee, working at first in facilities at Melbourne University then from later that year at Fishermans Bend when a new facility was opened there. His initial investigation was the chlorination of rutile found in Australian heavy beach sands which produced titanium tetrachloride; its importance in World War II then underway, was the dense white fume it produced on exposure to moist air, making it an effective smoke screen.
McTaggart's research in his position as Senior Principal Research Scientist headed a team including (in 1946) Ian Kraitzer, Chas Alsope, Margaret Ellis, Mick Bertrand and Joy Bear; and staff qualified in electronics; Keith Perger, appointed in 1962, replaced in 1968 by John A. Hamilton; and in glassblowing; in Port Melbourne Rudi Pillig transferred to the project from the Division of Chemical Physics, before which scientists including McTaggart and Newnham in the Minerals Utilization Section were themselves skilled glassblowers, and produced their own apparatus in glass or silica.