John Herschel Hardcastle

Major John Herschel Hardcastle (1870–1937) was an artillery officer in the British Army.

He became a ballistics expert and conducted experiments at the Royal Arsenal to devise data and formulae which were used for the army's official ballistic tables. He was himself a good shot and represented England in the Elcho Shield contest.

His middle name comes from his mother, who was the daughter of the astronomer and polymath, Sir John Herschel.