The Springfield Armory M1911A1 is one of the most frequently used handguns in the film (Which are clearly seen on the slides of the guns). At the beginning of the film, The Man (Josh Hartnett) uses a G.I. model fitted with a sound-suppressor to kill a woman. Marv (Mickey Rourke) also packs a G.I. model, which he affectionately named "Gladys", after a nun in his Catholic school. Apparently he took the gun from a guy he killed at school based on the line "I stole her off the toughest guy I ever messed with, back in school. He was dead at the time, so he didn't miss her." -(graphic novel Sin City: The Hard Goodbye"). Det. Jack "Jackie Boy" Rafferty (Benicio del Toro) packs a single G.I. model with Pearl grips and Dwight McCarthy (Clive Owen) carries two matching G.I.'s with ivory grips. Along with all of them, several random extras such as thugs and Old Town prostitutes are seen with M1911A1s as well.
The Painted Cop (Ryan Rutledge) brings a squad armed, like himself, with Micro Uzis to take out Marv (Mickey Rourke) at the Roark's farm. We later see both an Old Town prostitute and an IRA mercenary with Micro Uzis.
Douglas Klump (Rick Gomez) is the first character seen with the Beretta 93R Auto 9, aka the RoboCop gun. Hartigan (Bruce Willis) later takes Klump's Auto 9 and kills a cop with it at the Roark's farm. The Auto-9 seen in RoboCop was an actual Beretta 93R, but in the Sin City version of the gun, close inspection of the slide reveals a decocking safety of a Beretta 92FS, while a genuine 93R has a frame mounted safety, meaning this gun is a 92FS mocked up as an Auto 9. It was mentioned in a behind-the-scenes featurette that this particular weapon was used due to writer Frank Miller's involvement in the story for RoboCop 2 and RoboCop 3.
Roark Jr. a.k.a. Yellow Bastard (Nick Stahl) packs a Beretta 92FS when he follows Hartigan (Bruce Willis) to Kady's Bar and then fires it at Hartigan and Nancy (Jessica Alba) as they try to escape in her car. Several other thugs and Old Town prostitutes carry Berettas.
Murphy, the IRA mercenary that shoots McCarthy (Clive Owen) from the T-Rex uses a Steyr AUG. Later when they find the bullet in Rafferty's badge, the bullet is far too large to be a 5.56mm.
In the beginning of the film, Detective Hartigan (Bruce Willis) uses a Smith & Wesson Model 29 .44 magnum to rescue the young Nancy Callahan (Makenzie Vega), and also uses it to blow Roark Jr. (Nick Stahl) apart. Frank Miller made Hartigan use a .44 magnum as an ode to Dirty Harry and felt the 5th film was a bad way to end the series, so he made this as his Dirty Harry. Note how Nancy's last name is "Callahan." Despite being a lefty in real life, Bruce Willis was nice enough to fake being a righty shooter for the film to stay faithful to the comics.
In the beginning of the film, Bob (Michael Madsen) shoots his partner, Hartigan (Bruce Willis) with a Colt Python in the back and chest in fear of the Roark family's wrath. A hitman holds a Colt Python to Marv's back in Katie's Bar, and an Old Town prostitute can also be seen wielding one. Strangely Bob fires 8 shots out of his six shot Python, which doesn't happen in the book.
During the scene where Hartigan (Bruce Willis) is in a hospital room and Senator Roark (Powers Boothe) is telling him how he'll pay for shooting Roark Jr. (Nick Stahl), Senator Roark can be seen with a Colt Defender (a 3" 1911, if you look closely you can see the Colt "Ponies" on the slide before and after the words "Colt Defender"). It is clearly too small to be an Officers ACP or a Kimber as it was previously listed.
When Hartigan (Bruce Willis) returns from being in prison for eight years and meets up with the now nineteen year old Nancy Callahan (Jessica Alba), she gives him a stainless steel Ruger Blackhawk which he uses to shoot Roark Jr. a.k.a. Yellow Bastard (Nick Stahl) in the throat, and to kill a cop while going to rescue Nancy at the Roark family farm. Nancy herself wears a pair of stainless Ruger Blackhawks and some old town prostitutes are seen with them, noticeably Dallas the black masked Prostitute (Patricia Vonne).
In the beginning of the film, Detective Hartigan (Bruce Willis) packs a Colt Detective Special in an ankle holster as his "Spare Rod". He attempts to use it when he is shot several times by his partner, Bob (Michael Madsen), but is only shot again when he attempts to pull it out.
The first Walther P22 we see is in the hand of an Old Town prostitute, which is two-tone with either a compensator or a compensator-like shroud. The next one we see is the one that Hartigan (Bruce Willis) takes from Shlubb (Nick Offerman) which is also two-tone and is seen being affixed with a suppressor by Shlubb when going to pick up Hartigan. Hartigan's Walther P22 is notably seen while it's on the the seat of the stolen Ferrari next to Klump's (Rick Gomez) Beretta 93R Auto 9.
Walther P22 with stainless steel slide - .22 LR.Error creating thumbnail: File missingAn Old Town prostitute with a Walther P22, which is two-tone with a compensator and a laser device.Error creating thumbnail: File missingShlubb threads a suppressor on his Walther P22 when going to pick up Hartigan. (extended cut).Error creating thumbnail: File missingHartigan keeps Shlubb's Walther P22 on the seat of the stolen Ferrari along with Klump's Auto 9. It is confusing why Hartigan would resort to the stiletto knife when he clearly has a sound suppressed gun to use.
Smith & Wesson Model 19
Manute's henchman Stuka (Nicky Katt) packs a Smith & Wesson Model 19 with rubber grips. Manute (Michael Clarke Duncan) himself appears to use the same revolver in the alley before being shot several times. He then flees from the alley and is stopped by Miho (Devon Aoki), where he is seen using two Model 19s before she cuts him in half with a large blade spear type weapon.
In the beginning of the movie, Roark Jr. (Nick Stahl) carries a Colt Officer's ACP with a blued frame and stainless steel slide, which he uses to shoot Detective Hartigan (Bruce Willis) several times non-fatally and hold Nancy Callahan (Makenzie Vega) hostage but loses it when Hartigan blows his arm off on the dock.
A Mk. 2 hand grenade (likely just a plastic molded prop) is used by Brian (Tommy Flanagan) to send Dwight flying into the tar pits and to send Miho airborne, but not kill her.
