Manhunter is the 1986 cult film directed by Michael Mann which was the first theatrical adaptation of Thomas Harris' novel Red Dragon and the first (even before The Silence of the Lambs) movie appearance of Hannibal Lecter (named Hannibal Lecktor here), played by Brian Cox at this point.
The following weapons were used in the film Manhunter:
Charter Arms Bulldog is used by an FBI agent Will Graham (William Petersen) towards the middle of the movie in the scene, where running african-american mistaken for the serial killer "Tooth Fairy" and in the final scene, while shooting real "Tooth Fairy"/"Red Dragon" - Francis Dollarhyde (Tom Noonan).
Remington 870
A Remington 870 is used by serial killer Francis Dollarhyde (Tom Noonan) with a sawed-off buttstock to shoot up his house at the end of the film. He kills 2 cops, wounds Jack Crawford (Dennis Farina) and attempts to kill Graham (William Petersen) before he pumps 6 rounds into him with his Bulldog (though before Dollarhyde was also wounded by another cop's bullet).
Colt Commando
Used by cops at the middle and the end of the film.
Unknown suppressed pistol
Used by Francis Dollarhyde (Tom Noonan) to shot 3 times and kill Ralph Dandridge (Ralph Mandy in original novel), played by Bill Cwikowski).
The pistol is covered by something in most of the shots, so it's very difficult to say even what was used in this scene - pistol, or an unknown special effects device. Though, pistol anyway supressed (that's easy to know cause of it's sounds and facts listed about Dollarhide in the movie and in the novel)
Unknown Handgun
An unknown pistol is seen stuffed in Jack Crawford's (Dennis Farina) pants "mexican style." He never uses this pistol in the film. However, it is very unprofessional for a cop to have his gun stuffed in his pants like he did, perhaps Dennis Farina should have brushed up on his cop skills (as he was a Chicago police officer for 18 years) before doing this.
Unknown revolvers
Cops, killed by Dollarhyde were using unknown revolvers.
Unknown shotguns
Cops (including that one, ressembling Anthony Hopkins, who later will be playing Hannibal Lecter) using unknown shotguns in the film.
Unknown sniper rifle
Used by police in the scene with the running african american.