The M-7 is the Army's newest tank destroyer and is being given the acid test for desert warfare in the maneuvers near Iron Mountains, California. Colonel R. Downing of DeKalb, Missouri, Corporal L. Roberts from Graham, Texas, and Lieutenant M. Hutchison, Enterprise, Alabama. For firing power, the M-7 has a 105 mm Howitzer and a 50 caliber automatic gun. Iron Mountains, California.