Justified

Sig P226

During season 1 episode 1 "Fire in the Hole", Raylan Givens (Timothy Olyphant) uses a 9mm SIG P226 to shoot a suspect in Miami when he refuses to surrender and tries to shoot Raylan with a gun he had hidden underneath the table. Later in the episode Chief Deputy Art Mullen (Nick Searcy)uses a SIG P226 during the gunfight against Crowder's two "fat" Neo Nazi thugs.

Remington 870 or Mossberge 500 Cruiser

During season 1 episode 1 "Fire in the Hole", one of Boyd Crowder's Neo Nazi thugs Dewey Crowe (Damon Herriman) tries to intimadate Raylan by loading either a Remington 870 or Mossberge 500 Cruiser with pistol grip, vertical foregrip, and has a saddle shell holder attached to the left side of the shotgun's receiver. Dewey loads two rounds in the shotgun but forgets to rack in a load, in which Raylan calls himout and says "Can you rack in a load before I put a hole through it?" Later in the episode Raylan Givens (Timonthy Olyphant) takes Dewey's shotgun and fires one round to command Dewey and another of Crowder's Neo Nazis to handcuff themselves together before going off to confront Crowder.

A production still of Raylan Givens (Timothy Olyphant) seen with either the Remington 870 or the Mossberge 500 Cruiser with pistol grip and vertical foregrip

Remington 870 with pistol grip and vertical foregrip - 12 Gauge.

Mossberg 500 Cruiser with plain barrel, no heat shield - 12 gauge