Inspector Harry Callahan's (Clint Eastwood) primary weapon as expected is his ".44 Magnum", the Smith & Wesson Model 29 with an 8 3/8" barrel. He comments in the film to his partner Insp. Kate Moore (Tyne Daly) that he particularly favors this gun do to penetration power, since he claims he's seen a .38 ricochet off a car windshield.
Colt Diamondback
The 2" barrel version of Colt Python is carried by Callahan's partner, Inspector Kate Moore (Tyne Daly), who keeps it in her purse. This revolver is also carried by many members of the San Francisco Police Department.
Colt Trooper MK III
An SFPD officer is seen aiming his Colt Trooper MK III during the robbery at the beginning of the film.
Smith & Wesson Model 27
Callahan's first partner in the film, Insp. Frank DiGiorgio (John Mitchum), carries a large N-Frame Smith & Wesson Model 27 with a 4" barrel as his sidearm.
Ithaca 37
Bobby Maxwell (DeVeren Bookwalter) uses a sawed off Ithaca 37 shotgun to kill one of the gas station drivers at the beginning of the film. Later, an SFPD officer is seen using a full sized Ithaca while outside the liquor store being robbed.
M16 (SP1)
M16 (SP1) rifles (with both birdcage and three-prong flash hiders) are used by the SFPD officers that arrest the Uhuru group, and later are seen among the weapons stolen from the Hamilton Firearms warehouse by Bobby Maxwell (DeVeren Bookwater) and his terrorist group, The People's Revolutionary Strike Force. They later use the guns to abduct the Mayor (John Crawford) and hold him on Alcatraz.
Armalite AR-18 rifles were used by the members of Bobby Maxwell's terrorist group, The People's Revolutionary Strike Force, on Alcatraz Island.
Remington 870 Folding Stock
A nun in the church Harry goes to at the end of the movie to investigate the priest tries to fire a Remington 870 Folding Stock on him before being killed by Inspector Kate Moore.