On November 1, 1943, the 2nd and 3rd Raider Battalions spearheaded the initial invasion of Bougainville by the 3rd Marine Division. Sgt. Strank, M Company, 3rd Raiders, landed on Green Beach #2 at Cape Torokina and participated in the seizure and occupation of Empress Augusta Bay (Operation Cherryblossom). On January 12, the 3rd Raiders were removed from the combat zone and returned to Guadalcanal, arriving on January 14. On February 1, the 1st Marine Raider Regiment was redesignated the 4th Marine Regiment. The 3rd Raider Battalion was disbanded and designated the 3rd Battalion, 4th Marine Regiment. On February 14, Sgt. Strank was sent to San Diego and allowed a leave to visit his family.