U.S. Army Sgt. Christopher Rivas carries 155 mm rounds for a M777A2 howitzer during a live-fire exercise at the Joint Multinational Training Command's Grafenwoehr Training Area in Germany, April 30, 2015. Rivas is assigned to the 4th Battalion, 319th Airborne Field Artillery Regiment, 173rd Airborne Brigade. U.S. Army Sgt. Christopher Rivas carries 155 mm rounds for a M777A2 howitzer during a live-fire exercise at the Joint Multinational Training Command's Grafenwoehr Training Area in Germany, April 30, 2015. Rivas is assigned to the 4th Battalion, 319th Airborne Field Artillery Regiment, 173rd Airborne Brigade. SHARE: Download: Full Size (2.07 MB) Tags: Photo Essays Credit: VIRIN: 813318-L-SNT48-862.jpg Photo Gallery