As a composer, Bullock wrote mostly church music, including twenty anthems and motets, two settings of the Te Deum and two of the Magnificat and organ pieces.

Thomas and Eliza Bullock died when Ernest was still a boy, and Bairstow took charge of his musical and general education, taking him as an articled pupil and sending him to Wigan Grammar School.

The post was offered to Bairstow, who was by then master of the music at York Minster; he preferred to stay in Yorkshire, his native county, and, probably on his recommendation, Bullock was appointed to the Abbey.

Among the latter was the coronation of George VI on 12 May 1937, for which Bullock composed fanfares and acted as joint musical director, together with Sir Adrian Boult.

[9] The music-making on that occasion was described in the Dictionary of Composers for the Church in Great Britain and Ireland as the finest music ever heard in the abbey.

The Times later commented that Bullock's immediate predecessor in the dual role, W. G. Whittaker, had "for various personal reasons ... found some difficulty in making Glasgow academic music run smoothly."

[1] On the retirement of Sir George Dyson as director of the Royal College of Music, London in 1952, Bullock was appointed to succeed him.

[6] His output includes three evening services, two Te Deums, two Magnificats, a Jubilate, twenty anthems and motets, organ music and a small number of part-songs and other secular vocal pieces.