Capt Grandprey enlisted in the Marine Corps Reserve in June 2009. He served as a rifleman with Fox Company 2d BN 24th Marines in Milwaukee, WI from December 2009 to May 2013. While there, he served in a variety of billets including rifleman, automatic rifleman, team leader, and assistant patrol leader and achieved the rank of Corporal. During this period, he completed his Bachelor of Science in History at the University of Wisconsin – Oshkosh. He also graduated from the Marine Corps’ Officer Candidate School’s Platoon Leader Course Program which allowed him to commission as a Second Lieutenant.
After completing The Basic School and Infantry Officers Course in September 2014, 2ndLt Grandprey received orders for 1st Bn, 4th Marines, 1st Marine Regiment Reinforced, 1st Marine Division station on Camp Pendleton, CA. He served as a rifle platoon commander, weapons platoon commander, and company executive officer for Company C deploying in support of Marine Rotational Force – Darwin and the 11th Marine Expeditionary Unit (MEU). During his deployments, 1stLt Grandprey conducted bilateral interoperability training with the Royal Australian Army, Japanese Defense Force, and Malaysian Rangers. Additionally, he led the execution of company fire support planning across multiple exercises and integration of weapons platoon Marines for combat operations in Syria.
Shortly after return from the 11th MEU, 1stLT Grandprey received orders for the School of Infantry – West and promoted to his current rank of Captain in November 2017. Capt Grandprey served in multiple billets across Infantry Training Battalion and Marine Combat Training Battalion. Here, he had the privilege of leading the instructors who provided foundational infantry training to thousands of Marines throughout his three year tenure; some of which are now Noncommissioned Officers in Company E.
Capt Grandprey separated from active duty in June 2021 and was assigned to his current unit where he is honored with the opportunity to serve the Outlaws.