Both of the police officers who arrest bank robber Jack Foley (George Clooney) in Florida use Beretta 92FS pistols. U.S. Marshal Karen Sisco (Jennifer Lopez) later carries one as her standard sidearm when Foley takes her SIG P230.
SIG-Sauer P232
Karen Sisco recieves a SIG-Sauer P232 chambered in .380 ACP as a gift from her father (Dennis Farina), referring to it as the "SIG-Sauer .380".
Remington 870
Karen Sisco keeps a Remington 870 in her trunk, which she uses to assist during the Glades prison breakout. Buddy Bragg (Ving Rhames) gets ahold of it and uses it against her later in the scene. A federal marshal transporting Foley during the finale also has a Remington 870 Police Magnum.
subcompact pistol
Chino (Luis Guzman) chambers a round into a subcompact pistol with pearl grips when going to visit Adele (Catherine Keener), but Karen takes the pistol from him while arresting him.
Heckler & Koch MP5A2
One of the FBI task force members breaking into Foley and Buddy's room holds a Heckler & Koch MP5A2
Ithaca 37
One of the FBI task force members breaking into Foley and Buddy's room holds an Ithaca 37.
Colt Mk IV Series 70
Maurice "Snoopy" Miller (Don Cheadle) carries a M1911A1 as his standard sidearm throughout the film, referring to it as his ".45". However, the bore aperture is too small to be a .45 and it is more likely a Colt Mk IV Series 70 in 9 mm.
"White Boy" Bob (Keith Loneker) carries a nickel SIG-Sauer P226 as part of Maurice's crew. Maurice later grabs it to use against Foley.
Smith & Wesson 4th Model
Buddy carries a small top-break Smith & Wesson 4th Model during the robbery of Ripley's mansion. He later gives it to Foley, who uses it until it runs out of ammunition.
Smith & Wesson Model 442 Airweight
Kenneth uses a Smith & Wesson Model 442 Airweight as a secondary weapon during the Ripley robbery. Foley later grabs it to use when Maurice is after him, but empties out the bullets when he hears Karen's voice.
This is a S&W Model 38 with Harrett grips, the hammer is shrouded, not internal like a 442. - Gunmaster45