McCarty then returned to Pennsylvania and taught at St. Mary's College in North East from 1916 to 1917.[1] He taught at Mount St. Alphonsus Seminary in Esopus (1918-1926), where he also served as prefect of studies (1921-1930).[1] From 1930 to 1933, he was an assistant rector at the Mission Church in Boston, Massachusetts.[1] He then returned to Mount St. Alphonsus as its rector, serving between 1933 and 1939.[1] From 1939 to 1943, McCarty served as provincial of the Redemptorists' Eastern Province.[1] During his tenure as provincial, he inaugurated fourteen Redemptorist foundations in the United States, Puerto Rico, and Brazil.[3]
After twenty-one years of service, McCarty retired as Bishop of Rapid City on September 11, 1969; he was appointed Titular Bishop of Rotdon by Pope Paul VI on the same date.[2] He resigned his titular see on January 13, 1971.[2] He died in 1972, aged 83.