Blue Jones wielded a pistol to kill Amber and Blondie.
Colt 1911A1[]
Like Babydoll and her stepfather, Blue has a Colt 1911A1 with a brightly polished nickel-plating and pearl grips. He was seen with this weapon towards the end of the movie. CJ holds onto the weapon until "needed" such as when he used it to make unambiguous examples of the would-be escapists (Amber & Blondie in particular) in front of everybody -- minus Rocket (who was already dead) and Sweet Pea (who was locked in a utility closet).
Blue with his freshly drawn .45 auto colt
Blue kills Amber.
Blue kills Blondie.
Blue claims he hates guns.
Blue passes off the handgun to Danforth.
Now then, back to business...