.50 BMG, Browning Machine Gun. A heavy machine gun round, used in ground, vehicle and aircraft mounted machine guns since the 1920's. 1/2 in bore diameter, or .50 cal.
In the 80's, companies like Barrett and EDM developed bolt action, man portable rifles like those shown above, used for long range and anti-materiel sniping.
47 posted on 07/30/2004 8:33:41 AM PDT by xsrdx
(Diligentia, Vis, Celeritas)