She was laid down on 17 October 1943, under a Maritime Commission (MARCOM) contract, MC hull 1430, at the Permanente Metals Richmond Shipyard #4, Richmond, California.

[3] Casper sailed from San Francisco, California, on 30 September 1944, for a weather patrol out of Seattle, Washington, returning to San Francisco, 6 November.

From this base, she operated as plane guard, and on weather patrol, performing these vital functions between the mainland and Pearl Harbor.

During the organizing conference of the United Nations at San Francisco, which began 25 April 1945, Casper made two security patrols off the Farallon Islands.

[3] Casper cleared San Francisco, on 4 April 1946, for Charleston, South Carolina, where she was decommissioned on 16 May 1946.