The M1911A1 is the most commonly seen gun in the movie, used primarily by mob soldier Michael Sullivan (Tom Hanks). Connor Rooney (Daniel Craig) also uses an M1911A1 when murdering Finn McGovern (Ciaran Hinds) and, later, Sullivan's wife Annie (Jennifer Jason Leigh) and youngest son Peter (Liam Aiken).
(Whenever Sullivan uses this gun to kill Connor, the gun fires three times and, although casings are heard hitting the ground, none are seen leaving the pistol itself and the slide never retracts. Also, the gun is often seen firing with the hammer down, even though it is a single action pistol.) Additionally, during the hotel fight with Maguire, before Sullivan fires the shot that wounds the assassin, his 1911 is clearly out of ammunition, as the slide is locked back.
In some shots where an actor is required to fire the 1911 close to another actor, a 1911 "Non Gun" is substituted.
Colt 1911 Non GunError creating thumbnail: File missingSullivan shoots Connor with a 1911 "non-gun". The shape of it, as well as the fact that Sullivan fires it three times without it cycling and with only a flash emitting with each shot, gives it away as a "non-gun".
Thompson M1928 (corrected, note the compensator)
Michael Sullivan uses the .45 ACP Thompson M1928 submachine gun, popular with gangsters of the era, during the Finn McGovern murder and also to gun down John Rooney (Paul Newman) and his gangsters towards the end of the movie.
Calvino (Doug Spinuzza) puts a S&W Hand Ejector under a magazine when his bodyguard (Kevin Chamberlin) tells him that Sullivan is there. Sullivan then grabs it and uses it to shoot both Calvino and the bodyguard, presumably leaving it on the desk when he leaves.
Calvino's bodyguard (Kevin Chamberlin) draws a small frame revolver inside Calvino's office but is killed by Sullivan before he has a chance to fire it.
Michael Sullivan (Tom Hanks) gives a .38 Colt Detective Special to his son when he goes in to kill Kelly, telling Michael Jr. that he's "got six shots" if he needs them. At the film's end, a dying Sullivan uses the same revolver to kill Maguire.
Hitman Harlen Maguire (Jude Law) uses a .32 ACP Savage 1907, shooting Sullivan in the shoulder after the hotel shootout. Michael Sullivan, Jr. (Tyler Hoechlin) picks up this gun at the end of the movie but does not fire it.
Harlan Maguire (Jude Law) carries a Winchester Model 1897 shotgun under his jacket when he goes to kill Michael in the hotel. He ends up killing Rance, the mob accountant, but missing Michael.
When Sullivan is mowing down John Rooney (Paul Newman) and his thugs outside O'Neill's bar, most of Rooney's men carry 1911s but one fires back at Sullivan with a Smith & Wesson Model 10.
