A nickel plated Colt Detective Special is carried by Chicago patrolman George Stone (Andy Garcia) as his backup gun, which he tosses to Ness during the train station shootout.
The revolver used in each of these scenes is not a D frame Colt Police Positive but in fact the larger I/E frame Colt Official Police. The size of the gun in Ness (Costner) and Stone's (Garcia) hand is too large for the smaller D frame Police Positive
Officer Stone (Andy Garcia) uses a Colt Police Positive while on the police academy firing range. The court officer is later seen with one that he lends to Ness for him to chase Nitti down.
More evidence that this is a Colt Official Police in this scene that shows Ness holding the gun from a side view. If the image had been taken a moment later, the viewer would have a chance to see that the hammer matches an Official Police hammer and is different from the Police Positive hammer seen in the image at the top. What is even more interesting about this gun is that this particular version of the Official Police is actually a Post-War gun (wasn't made until after 1950) whereas this movie takes place in the 1930s. The ramped front sight, flat hammer and longer ejection rod cap are changes that were made after 1950. Pre-War guns would have a halfmoon front sight and shorter ejector rod cap,
M1911
Treasury agent Elliot Ness (Kevin Costner) uses a M1911 throughout the film. Treasury accountant Oscar Wallace (Charles Martin Smith) keeps one in a shoulder holster. Frank Nitti (Billy Drago) carries a nickel-plated Star Model B in court, which Ness uses as an excuse to kick him out. Several other of Capone's (Robert De Niro) mobsters carry them.
A Smith & Wesson Model 10 is carried by Stone (Andy Garcia). He uses it to kill the gangster who is holding the bookeeper hostage at the end of the shootout in the train depot. Malone (Sean Connery) also carries one, which he infamously uses to shoot an already dead gangster. Many other Chicago policemen carry Model 10s.
A gangster who holds the bookkeeper (Jack Kehoe) from Ness and Stone in the train station holds a Star Model B to the bookkeeper's head.
Ness (Costner) also used one himself in some of the firing scenes. LMO has a picture of the Star Model B used by Kevin Costner in some scenes of the movie. -MT2008
Many gangsters and policemen use the Thompson M1928 during the film. Stone and Malone use them to great effect during the Canadian shootout. Frank Nitti notably uses one to fatally wound Malone outside his apartment.
According to the Ellis Props & Graphics NFA weapons list available on Long Mountain Outfitters' web site, there was a mix of M1921s and M1928 Thompsons used in the film. -MT2008
Error creating thumbnail: File missingLee-Enfield No.1 Mk.III* - .303 British. This was the main battle rifle of British and Commonwealth forces during the First World War, introduced in 1907 it has seen action throughout the 20th century.
Error creating thumbnail: File missingM1917 Enfield .30-06. The Pattern 1914 was chambered originally in a high velocity .276 caliber and then changed to .303 British when the experimental caliber proved to be troublesome. Remington manufactured the rifle for the British in WW1. After the U.S. joined the Allies it was easy to convert the rifle to 30-06. Which was important since the Federal Springfield Armory could not produce enough of the 1903 Springfield rifle to meet war demands.United States troops carried both the 1917 Enfield and the 1903 Springfield in World War I.
A Winchester Model 1912 is used by Elliot Ness (Kevin Costner) during the shootout in the train station. These are also used during the shootout on the Canadian/U.S. border.
An 12 Gauge Rossi Overland sawed-off shotgun is kept by Malone (Sean Connery) in his apartment as a "home defense" weapon. The Rossi Overland sawed-off shotgun was built by the late gunsmith Branko Wohlfahrt for Ellis Mercantile.
