SgtMaj Gregg assumed duties as the command senior enlisted leader of Marine Corps Logistics Command in May 2025.
He enlisted in the U.S. Marine Corps in June 1998 and completed recruit training at Marine Corps Recruit Depot Parris Island, South Carolina. He went on to receive infantry training at Infantry Training Battalion, School of Infantry East, earning the military occupational specialty of 0311, rifleman. He then completed Marine Security Force School in Chesapeake, Virginia, and was awarded the 8152 secondary MOS.
In 1999, he reported to Second Fleet Anti-terrorism Security Team (FAST), Yorktown, Virginia. During this assignment, he deployed twice to Naples, Italy in support of Marine Corps Security Mission Europe, and to Kosovo and Macedonia in support of Operation Joint Guardian and U.S. Embassy security operations.
In 2002, he was assigned to Marine Barracks Washington, D.C., where he was promoted to Sergeant and served as sergeant of the guard.
In 2003, he reported to 2nd Battalion, 8th Marine Regiment and deployed to Korengal, Afghanistan, in support of Operation Enduring Freedom; to the Middle East with the 26th Marine Expeditionary Unit (Special Operations Capable); and to Fallujah and Rawah, Iraq, in support of Operation Iraqi Freedom. During these tours, he served as squad leader, element leader, and platoon sergeant, and was promoted to Staff Sergeant.
In 2007, he attended Marine Combat Instructor School and the Formal School Instructor Course before being assigned to School of Infantry East. There, he served in multiple instructional roles, including combat instructor, platoon commander, chief combat instructor, master instructor, weapons section chief instructor, and company gunnery sergeant. He was meritoriously promoted to Gunnery Sergeant during this tour.
In 2011, he reported to Weapons Company, 3rd Battalion, 4th Marines, 7th Marine Regiment, where he served as combined anti-armor team platoon sergeant, weapons company operations chief, and weapons company first sergeant. He deployed to Kajaki, Afghanistan, in support of Operation Enduring Freedom and was promoted to First Sergeant.
In 2014, he reported to Marine Corps Logistics Command, where he served as Headquarters Company-East first sergeant and Headquarters Group command senior enlisted leader.
In 2017, he reported to 3rd Marine Raider Battalion, Marine Corps Forces Special Operations Command as the company first sergeant for Marine Special Operations Company-L. He deployed to Somalia in support of Special Operations Command-East Africa and Operation Octave Shield. While assigned to the battalion, he was promoted to his current rank.
In May 2019, he assumed duties as the command senior enlisted leader of Marine Light Attack Helicopter Training Squadron 303, 3rd Marine Aircraft Wing.
In January 2022, he assumed duties as the command senior enlisted leader of 2nd Battalion, 11th Marines, 1st Marine Division.
In April 2023, he assumed duties as the command senior enlisted leader of Headquarters and Support Battalion, Marine Corps Installations East, Marine Corps Base Camp Lejeune.
SgtMaj Gregg’s personal awards include the Legion of Merit, Meritorious Service Medals, Joint Service Commendation Medal, Navy and Marine Corps Commendation Medals, Joint Service Achievement Medal, and Combat Action Ribbons.