Illinois Gordon (Chi McBride) gives his cousin Bumpy Johnson (Laurence Fishburne) a Colt Official Police revolver, which he uses throughout the entire movie to take over Harlem. At one point, Bumpy's girlfriend Francine (Vanessa Williams) is forced to shoot assassin Albert Salke (Mike Starr) with the revolver.
Many of the Harlem gangsters in the film use M1911A1s. Whispers (Paul Benjamin) carries two, one on each hip, that he draws several times. Dutch Schultz (Tim Roth) and his bodyguard, Lulu Rosencrantz (Ed O'Ross) both carry 1911s, one of which is eventually used by Lulu to shoot his boss in the Palace Chop House bathroom.
It looks like Schultz's 1911 is a Series 70, which would not have existed back then, so its presence in the movie is an anachronism.
Illinois Gordon (Chi McBride) carries a nickel Smith & Wesson Model 10 snubnose revolver, which he gives to Bumpy before his death at the hands of Capt. Foley.
Albert Salke (Mike Starr) and Jules Salke (Beau Starr) use a "silenced" revolver to kill the guard at Bumpy's building during their attempted hit, following the classic movie myth of having a suppressor work on a revolver.
Dutch's gunmen use Thompson M1928s during their attempted hit on the Queen and Bumpy. After killing one of the hoods, Bumpy picks up the Thompson and fires back at them with it.
Bub Hewlett (Clarence Williams III) carries a sawed-off Remington 870 when Dutch's men raid the apartment at the end. He also uses one during the attempted hit on Queen Stephanie before tossing it away. Several other sawed-off 870 shotguns are used, some without their stocks.
Queen Stephanie's bodyguard, Tee-Ninchy (Eddie Bo Smith Jr.) caries a sawed off Ithaca 37 as his weapon of choice. He carries it with him, (and nearly uses it) during the meeting between Queen Stephanie, and Dutch Schultz. He also uses it to kill several hitmen during the attempted hit on the Queen before being shot to death. When Bumpy and Whispers gain the upper hand during the shootout, Bumpy picks it up and uses it to (unrealisticly) set a nearby truck ablaze. Before the hit, one of the Queen's guards can also be seen holding this weapon.