Sergeant Major Amancio reported to MCRD San Diego, California for recruit training in January 1997. Upon graduation, he attended Marine Combat Training and then proceeded to Marine Corps Engineer School, Court House Bay, Camp Lejeune, NC to Utilities Instruction Company. In July 1997, Private First Class Amancio was assigned to 2d Maintenance Battalion, Engineer Maintenance Company, Utilities Platoon. During his assignment, he served in billets such as Water Equipment Technician, Quality Control NCOIC, and Platoon Sergeant. In addition, he deployed with Combat Service Support Detachment 69 in support of hurricane disaster relief, Operation FUERTE APOYO, in El Salvador, Nicaragua, and Guatemala. He was promoted to the ranks of Lance Corporal, Corporal (meritoriously) and Sergeant during his tenure with 2d Maintenance Battalion.
In May 2001, Sergeant Amancio reported to Chemical Biological Incident Response Force (CBIRF), Naval Surface Warfare Center, Indian Head, MD. Billets performed were Utilities Operations NCOIC, Platoon Sergeant, Battalion Color Sergeant, and Battalion Training Chief. During his tour with CBIRF he executed multiple high security national events; such as the world Summit Meeting in NYC and Presidential State of The Union Address. In addition, he assisted in Operation NOBLE EAGLE as result of the anthrax findings on Capitol Hill. While assigned to CBIRF he was promoted to Staff Sergeant (meritoriously).
In November 2003, Staff Sergeant Amancio executed orders to Marine Wing Support Group 17, Marine Wing Support Squadron 171, Iwakuni Japan. He served with Engineer Operations Company and performed duties as the Utilities Operations Chief. During his assignment he participated in exercise FOAL EAGLE in Korea. While assigned to 171, he requested and received orders to Drill Instructor School for January 2005, MCRD San Diego CA. Upon graduating, Staff Sergeant Amancio served as a Drill Instructor, Senior Drill Instructor for Bravo Company, 1st Recruit Training Battalion and as a Instructor and Chief Instructor of the Martial Arts Section.
In April 2008, concluding his tour on MCRD, now Gunnery Sergeant Amancio, reported to 8th Communication Battalion, Camp Lejeune, NC and held the billets of Utilities Chief, Operations Chief for Engineer Platoon and served as the Company Gunnery Sergeant for Headquarters Company. During his tour, he deployed in support of Operation IRAQI FREEDOM, and Operation ENDURING FREEDOM. Upon return from deployment, in May 2012 he was frocked to First Sergeant and executed orders to MCRD San Diego, CA where he was assigned to Golf Company, 2d Recruit Training Battalion to serve as the Company First Sergeant.
In June 2014, First Sergeant Amancio attended the United States Army Sergeants Major Academy (USASMA), Fort Bliss, TX. As a student, he completed a ten-month academic curriculum focusing on: Unified Land Operations, Command Leadership, Force Management, Training and Doctrine, Military History, and Joint, Intergovernmental, Inter-agency, and Multinational Operations. Upon graduation from USASMA in June 2015, First Sergeant Amancio received and executed orders to 2d Battalion, 8th Marines "Americas Battalion", 2d Marine Division, Camp Lejune, NC. There he served as the Company First Sergeant for Golf Company and Headquarters and Service Company. During his assignment with 2d Battalion, 8th Marines he deployed in support of the Black Sea Rotational Force 16.2 to Mihail Kogalniceanu, Romania participating in numerous coalition exercises. While deployed he was selected to his current rank and received orders to recruiting duty.
In April 2017, Sergeant Major Amancio executed orders to Watervliet, NY where he was assigned to 1st Marine Corps District, Recruiting Station Albany, NY. There he served as the Recruiting Station Sergeant Major. In August 2020, Sergeant Major Amancio reported to Iwakuni, Japan, 1st Marine Aircraft Wing, and serves as the Marine Aircraft Group 12 Sergeant Major. Sergeant Major Amancio's personal awards include the Meritorious Service Medal, Navy and Marine Corps Commendation Medal with four gold stars, and Navy and Marine Corps Achievement Medal with one gold star.