Green tip, M855 5.56mm ammunition is photographed Monday, March 2, 2015, in Fort Washington, Md. The Bureau of Alcohol, Tobacco, Firearms and Explosives is proposing the ban of &amp;#xec;M855 green tip&amp;#xee; or &amp;#xec;SS109&amp;#xee; rounds with certain types of metal cores. (AP Photo/Alex Brandon) Photo: AP / AP