(from the article `Dum Dum`) The best known of the towns is Dum Dum, founded in 1783. It was the headquarters of the Bengal artillery until 1853 and has an ammunition factory in ... ...soft steel jacket. In rifle and machine-gun bullets, a soft core of lead is encased in a harder jacket of steel or cupronickel. Armour-piercing ... ..... Found on http://www.britannica.com/eb/a-z/d/81