Navy Hospitalman Hammett was attached to the 1st Marine Division in Korea. He was Wounded in Action while tending his wounded comrades in the Seoul area of South Korea and evacuated to the Medical Battalion Hospital where he died of those wounds on 1 October 1950.

Hammett was awarded the Purple Heart, the Combat Action Ribbon, the Korean Service Medal, the United Nations Service Medal, the National Defense Service Medal, the Korean Presidential Unit Citation and the Republic of Korea War Service Medal.