Crozier graduated from the United States Military Academy at West Point, New York in 1876, and was appointed a second lieutenant in the 4th Artillery.

In 1888 he was sent by the War Department to study recent developments in artillery in Europe, and on return he was placed in full charge of the construction of gun carriages for the army.

With General Adelbert R. Buffington, a future Chief of Ordnance of the United States Army, he invented the Buffington–Crozier disappearing gun carriage (1893).

He also oversaw and authorized donation and sale of various condemned cannon for use in town centers, soldier's monuments, and posts for fraternal organizations such as the Grand Army of the Republic.

[citation needed] His Notes on the Construction of Ordnance, published by the war department, were used as text-books in the schools for officers, and he also authored several other important publications on military subjects.

He also played a role in the rejection of the Lewis Gun by the Army, although it was quickly adopted by the British and used effectively through both World Wars.

During 1918 these charts were used in the United States arsenals, in the production of naval aircraft, and in other government work, such as that of the Emergency Fleet, the Shipping Board, etc.

On her death the 2 August 1955, Mary Hoyt Crozier (the daughter of New London, Connecticut mayor Charles Augustus Williams) left $300,000 to West Point to build a memorial hall.