GRENADE LAUNCHER Army Lt. Col. Christopher M. Rizzo fires an MK 19 automatic grenade launcher at a range on Joint-Base Lewis McChord, Wash., July 10, 2014. Rizzo, who commands Headquarters and Headquarters Battalion, I Corps, was familiarizing himself with the launcher as part of the shift of his unit's mission as an expeditionary force in the Pacific. SHARE: Download: Full Size (0.06 MB) Credit: VIRIN: 735877-M-PFH25-662.jpg Photo Gallery