The Winter War (Talvisota) is a Finnish movie from 1989. The film begins with the mobilization of the Finnish Army in October 1939 and ends on 13th of March 1940 with the Moscow Peace Treaty. We follow a few soldiers from their mobilization through the trench warfare and massive Soviet artillery barrages until their surrender. It's the most costly Finnish film to date and its historically very accurate considering they interviewed Finnish veterans prior to the filming.
This weapon is never seen used on film, but the holster of the Mauser C96 (which holds presumably the gun itself) can be seen on the belt of a Finnish officer in few scenes.
Luger P08
The Luger P08 makes an apperance at the end of the movie in the hands of a Finnish officer.
Tokarev TT-33 Pistol
2nd Lieutenant Jussi Kantola (Vesa Vierikko) carries a Russian Tokarev TT-33 Pistol
Rifles
Mosin Nagant M1891/30
The Mosin Nagant M1891/30 is the main rifle used by Red Army soldiers throughout the film. The rifle is also seen in the hands of some Finnish soldiers. Historically the Finnish Army during the war had a severe lack of equipment and weapons and they used Russian weapons whenever practible.
Finnish M/28-30 Civil Guard Mosin-Nagant Rifle
The main character, Martti Hakala (Taneli Mäkelä) uses the M/28-30 Civil Guard Mosin-Nagant Rifle, including his brother Paavo (Konsta Mäkelä), and a few other characters are members of Suojeluskunta ("Civil Guard", also known as "White Guard"). The "White Guard" was a voluntary militia and training organisation for reservists. In the beginning of the movie, the Hakala brothers are seen leaving their home as the Finnish army mobilizes, and they bring with them their own M/28-30 rifles. The M/28-30 was a Mosin-Nagant variant designed by the White Guards, and can be distinguished from other Mosin-Nagant rifles by their distinctive foresight guards and shorter stocks, among other things. It is similar to the M/27 Infantry Rifle adopted earlier by the Finnish Army, the main differences being the barrel band design, which is a single piece compared to the M/27's hinged band, and an improved trigger design. A major improvement over its Civil Guard predecessor, the m/28, was the straight Mansner rear sight and screw-adjustable front sight.
Mosin-Nagant Model 1891 Rifle
Several Finnish soldiers can be seen using earlier Model 1891 rifles. The rifles are either Russian M91s, Finnish M91s, Finnish M24s, or Finnish P26s.
Tokarev SVT-40 Rifle
The Tokarev SVT-40 Rifle is seen in the hands of both Russian and Finnish soldiers as a stand-in for the historically correct SVT-38. The Finns did use captured weapons such as the SVT-38 due to a lack of equipment and weapons. The Red Army used the version, SVT-38, in the Winter War, and the SVT-40 did not enter service until July 1940, several months after the end of the conflict. However, since SVT-38 is a much rarer weapon, it's understandable that the SVT-40 is being used as a "stand-in" for it.
Submachinegun
Suomi KP/-31
The standard SMG of the Finnish Army was the Suomi KP/-31 and it is frequently seen during the movie.
Light machine gun
Lahti-Saloranta LS/26
Lahti-Saloranta LS/26, the standard light machine gun of the Finnish army in that period, is used by the Finnish soldiers.
Degtyaryov Dp-27/28
The DP LMG is used by both the Red Army soldiers and the Finnish soldiers.
Explosives
Finnish stick hand grenade M/32
The Finnish soldiers during the move make good use of the stick hand grenade M/32.
Molotov Cocktail
The Finns are also seen using the "Molotov Cocktail" against tanks. The "Cocktail" was an historical incendiary device named after the Soviet Foreign Minister Vyacheslav Molotov. It is basically a bottle filled with a mixture of incendiary substances and has a stick-fuse attached to the side for ignition.