True Grit (1969)
True Grit is the classic 1969 Western that starred John Wayne as Deputy U.S. Marshal "Rooster" Cogburn, who is hired by a young girl to hunt down the man who murdered her father. Wayne returned to the role in the 1975 sequel, Rooster Cogburn, which co-starred Katharine Hepburn. The film would go on to receive two Academy Award nominations, with Wayne receiving his only Academy Award for Best Actor. The film was based on the Charles Portis novel of the same name, which was adapted again as a 2010 feature film with the Coen Brothers directing and Jeff Bridges in the role of Cogburn.
The following firearms were used in the film True Grit:
Single Action Army
Deputy U.S. Marshal Reuben J. "Rooster" Cogburn (John Wayne) keeps a Colt Single Action Army or "Peacemaker" with a 4 3/4" barrel, known as the "Civilian" or "Quick Draw" model, and fitted with mellow aged ivory-style grips as his sidearm of choice throughout the film. "Lucky" Ned Pepper (Robert Duvall) also keeps a Quick Draw Peacemaker which he uses when facing Rooster during the film's climax. While watching Rooster load his Peacemaker, Mattie Ross (Kim Darby) asks him why he keeps one chamber empty, to which he replies, "So I won't shoot my foot off." Carrying a single-action revolver with the hammer resting on an empty chamber is in fact a good safety method, because if the hammer were resting on a loaded chamber and something strikes the hammer, the gun could discharge and possibly cause some kind of injury. Rooster wields his Peacemaker with his Winchester Model 1892 rifle in akimbo at the climax of the film.
At one point in the film, Rooster tells Mattie about how when he was in the Civil War, he did the same dual wielding guns method while on horseback. He claims he fired two "Navy sixes" with the reins in his teeth. The two "Navy sixes" he mentioned using were either a pair of Colt Model 1851 Navy Revolvers - .36 caliber (or one of it's many Southern copies, such as the Griswold & Gunnison Revolver since Rooster fought for the Confederates), a pair of Colt Model 1861 Navy Revolvers - .36 caliber, or one of each. It is possible they were a pair of .36 caliber "Navy" versions of the Remington Model 1858 New Army or a pair of .36 caliber Navy versions of the Starr Model 1858 Double-Action Revolvers, but this is unlikely as the Starr revolver was unpopular and the Colt Navy and Army revolvers and the Army version of the Remington 1858 were more commonly used than the .36 caliber variants of the Remington Model 1858 in the Civil War.
John Wayne actually used three identical Colt Single Action Army revolvers in this film. Two of them were rented to him by the company called Stembridge. They were genuine Colt Single Action Army revolvers and one of them was either chambered for .44-40 Winchester Center Fire or .45 Long Colt, while the second one was definitly chambered for .45 Long Colt. The third one was Waynes own personal gun. Although he owned many Colt Single Action Army revolvers, this gun, serial number 309795, was the only one of his personal Colt Single Action Army revolvers he used in his films. This gun did most of the shooting in his films. Even though it was always billed as a .45 Colt, it was chambered for .44-40 WCF in reality. The interesting part is, this gun (serial no. 309795) didn't leave the factory as a regular Colt Single Action Army. It was originally a Colt Single Action Army "Bisley Model" with a 5.5 inch "Artillery" barrel, and was chambered in .45 Long Colt. It was later rebuilt to resemble an average Colt Single Action Army with a "Civilian"/"Quickdraw" Model barrel and was converted to fire .44-40 WCF cartridges. All three of these guns were fitted with ivory-style grips (manufactured by Maurice D. Scarlac out of a material he developed called Catalin). Wayne like them so much that he took these grips home and personally "tea-stained" them to give them that desirable "mellow aged ivory" look. Two sets of these grips were made for Wayne (the second set being a spair just in case if the first set broke). These grips all had three finger grooves in the left-hand side of the grips for Wayne middle, ring, and "little" fingers of Wayne's right hand for as they wrapped around the revolvers grip frame. The grooves can be clearly seen in the climactic gunfight between Rooster and "Lucky" Ned Pepper and his gang when Rooster has the gun tucked in his waist band.
For more information about John Wayne's SAA revolvers, go to the following link: 
Winchester 1892 "Saddle Ring Carbine"
Rooster Cogburn (John Wayne) keeps a Winchester 1892 "Saddle Ring Carbine" with a large lever loop chambered in .44-40 as his rifle of choice throughout the film and is most notably seen using it during the film's climax when he fires it akimbo style along with his Single Action Army, twirling the rifle with the large lever loop to cock it with one hand. (This action most likely inspired the same technique used by Arnold Schwarzenegger with the Winchester Model 1887 shotgun in T2). Wayne and stuntman Yakima Canutt created the so-called Hollywood lever for the movie Stagecoach. It was a technique refined by Chuck Connors in TV's Rifleman and Connors was clearly the master of spin-cocking a model 1892(easy for Connors who was 6' 5" tall).
Colt Walker 1847
Mattie Ross (Kim Darby) inherits her father's civil war handgun when he dies, which is a Colt Walker 1847. Mattie uses it when she encounters Tom Chaney (Jeff Corey) and is knocked down by the recoil of the gun (which is a bit unrealistic) and manages to shoot him in the gut with it. He then manages to charge her and take the gun due to several misfires (which were Rooster's fault, as he had loaded it incorrectly while drunk, and also overloaded the chambers with powder which caused the tremendous recoil). The gun manages to fire once more in the hands of Mattie and grazes Chaney's head though the recoil knocks her into a snake pit. When Mattie first shows the gun to Rooster, he calls it a Colt's Dragoon but it is clearly too large and lacks a loading lever latch that the Dragoon models had. Also the Walker has no percussion nipples showing that it is firing cartridges.
Sharps 1874 Cavalry Carbine
La Boeuf (Glen Campbell) uses a Sharps 1874 Cavalry Carbine as his rifle of choice throughout the film. When hunting, he manages to pretty much destroy a Turkey with the rifle. Later in the film he manages to shoot Ned Pepper's horse from a long distance and is mocked by Rooster for missing the shot claiming, "Maybe next time if you aim for for the horse, you might hit Pepper." He fairs better at the film's climax and manages to shoot Pepper off his horse from an impressive distance before he can kill Rooster.
Colt New Service (mock-up)
Lucky Ned Pepper (Robert Duvall) is seen in a few scenes using a Colt New Service revolver mocked up to look like a Single Action Army by adding a fake ejector rod. (See also The Long Riders.) These guns were used by actors too slow to handle a single action only revolver and required a double action trigger pull for quicker shots. It is strange why he uses this gun as he is never required to fire it rapidly and when facing Rooster at the end of the film, the gun switches to an actually SAA instead.
Winchester 1866 "Yellow Boy" (mocked up like Henry 1860)
Tom Chaney (Jeff Corey) is seen using a Winchester 1866 "Yellow Boy" rifle with the forend removed to look like a Henry 1860 rifle to murder Frank Ross (John Pickard), Matties' father. Dialogue confirms they intended the gun to be a Henry rifle in the film. Later, Chaney is seen with an actually Henry instead.
12 Gauge Double Barreled Shotgun
A U.S. Marshal helping Rooster Cogburn unload the outlaws from the Indian territory is armed with a 12 Gauge Double Barreled Shotgun. Later, Farrell Parmalee (Kenneth Becker) is seen armed with a side-by-side as well.
Winchester 1894 Saddle Ring Carbine
A U.S. Marshal helping unload outlaws from the Indian territory is seen armed with a Winchester 1894 Saddle ring Carbine rifle. He is seen with it in hand when telling Mattie to wait another day to talk to Rooster Cogburn. Later in the film, Ned Pepper is seen with a '94 rifle and fires it into the air to let Rooster know where he is. It clearly has a longer receiver and the more complex lever system under the gun helping tell it from an 1892 rifle.