The Guns the Brazilian Gangs use come mostly from Bolivia. Most drugs come from Bolivia also. What is funny about Bolivian drugs, is that Bolivian drug dealers don't sell them here in Brazil. They come here to export them to European Countries and to the United States since Bolivia is a Landlocked country.
Anyway, most Gangs today use old as shit FN FALs. Metric ones, mostly from corrupt Bolivian Army personnel. Most AKMs, Type 56s, AK-74s, Even Galils and AR-15 type guns come from Bolivia. On the other hand, the Military Police is more well armed than the Gangs. Hell, BOPE alone are more well armed than the fucking Brazilian Army:
http://en.wikipedia.org/wiki/Batalh%...iais_Especiais
And that's not all their equipment. They got Imbel MD97s and APCs. They are hardcore.