Sergeant Major Lunsford enlisted in the Marine Corps in July 1989. After completion of Recruit Training in 1990, he reported to the School of Infantry and graduated as an 0351 anti-tank Assaultman.

In January 1991, Private First Class Lunsford received orders to Bravo Company, Marine Barracks, Subic Bay, Republic of the Philippines. While assigned to Bravo Company, he served as a sentry, Patrol Team Leader, Corporal of the Guard, and Sergeant of the Guard.

Upon the closure of Subic Bay Naval Base in November 1992, he was transferred to 1st Battalion, 9th Marines (1/9) and assigned to Charlie Company as a SMAW gunner and team leader.

Post-deployment, and as 1/9 was re-designated 2d Battalion, 1st Marines (2/1), Corporal Lunsford was assigned to Weapons Company 2/1 as a Combined Anti-Armor Team squad leader.

In July 1996, Sergeant Lunsford reported to Drill Instructor School at Parris Island, South Carolina. Upon graduation, Sergeant Lunsford was assigned to Charlie Company, First Recruit Training Battalion. During his tour, he served as a Drill Instructor and Senior Drill Instructor.

In May 1999, Staff Sergeant Lunsford received orders to 3d Battalion, 5th Marines. While assigned to India Company, he served as a Platoon Sergeant, Platoon Commander, and Company Gunnery Sergeant.

In August 2002, Gunnery Sergeant Lunsford was transferred to Parris Island and assigned to Lima Company, 3d Recruit Training Battalion, where he served as a Senior Drill Instructor, Series Gunnery Sergeant, and Operations Chief before being assigned as an Instructor at Drill Instructor School.

Gunnery Sergeant Lunsford was promoted to First Sergeant in March 2005 and transferred to Echo Company, 2d Recruit Training Battalion, as the Company First Sergeant until December 2005.

First Sergeant Lunsford reported to 2d Transportation Support Battalion, 2d Force Service Support Group in January 2006. He served as the Company First Sergeant of Beach and Terminal Operations Company and General Support Motor Transport Company until being assigned as the Battalion Sergeant Major for Combat Logistics Battalion 22 from July 2006 until March 2010.

Sergeant Major Lunsford was promoted to his current rank in December 2009 and served with Combat Logistics Battalion 8 from March to July 2010. Sergeant Major Lunsford was later assigned as the Squadron Sergeant Major for HMH-464 from July 2010 to May 2012 and Sergeant Major at Marine Corps Detachment, Fort Lee, Virginia from May 2012 to October 2014. He served as the 8th Marine Regiment Sergeant Major from October 2014 to November 2016.

Sergeant Major Lunsford reported to his present duty as the Sergeant Major for 2d Marine Logistics Group on 1 December 2016.