H&K 93 semi-auto in 5.56mm used by the Norwegian to try and kill the infected dog while flying from the helicopter.
Ithaca 37 pump action shotgun
Not a Remington Model 31 as prevously mentioned. You can tell it is a Ithica 37 because of the lack of an side ejection port and the . It is also used to shoot the dogs and Windows manages to grab one before he is subdued by the others. MacReady (Kurt Russel) is also seen with one at the Norwegian base.
Smith and Wesson Model 15
Garry (Donald Moffat) uses the S&W Model 15 to shoot the Norwegian when he is trying to kill the infected dog with the H&K 93
Uknown flamethrower
This flamethrower is used by several members of the team throughout the movie.
Unknown grenade
This grenade is used by one of the Norwegians. It slips from his hand, and on explosion it kills his colleague and destroys the helicopter.
-this page is incomplete, please help me finish it.