Joe Knapp retired from the United States Marine Corps as a Colonel with over 24 years of service, including tours at Weapons Training Battalion (MCRD Parris Island), and as a Combat Advisor to the Iraqi Police and Iraqi Border Police during Operation Iraqi Freedom. He has attended numerous military, law enforcement, and civilian weapons training courses and is a certified NRA Law Enforcement Handgun/Shotgun and Patrol Rifle Instructor. Upon retirement from the Marine Corps in 2011, his 22nd Award Pistol Expert Award qualification was the highest held by any serving Marine and the second highest in Marine Corps history. He has been an Adjunct Instructor at Gunsite since 2009.