I believe american iron and metal will buy it, I know a couple of guys who have taken 5 gal. buckets of old lead and copper bullets to them in the past, but it has been a year or more. if not dionisio's might as well, but american pays cash the latter pays by check so just for the sake of time involved cashing a check I would try american first.
http://americanironmetal.com/scrap-m...ions/pueblo-co
http://www.dionisiometal.com