Although the term "bling bang" was first introduced by the movie "Blood Diamond" and originally referred to a type of diamond and not guns directly, the term has morphed and is often used on the Urban Street as a term for a flashy gun.
Synonym: Pimp Gun.
Malik, I got some Bling Bang for sale, bro, It's a chrome Deagle Fity. I took Jo-Jo out of da box, yo, and you can have his Bling Bang fo five benjamines - can't beat dat!
I scored big, now I can buy me some serious Bling Bang.