In keeping with the 'Steam punk' style of the film's technology (of the year 2207 AD) a lot of the soldiers look like a mish mash of World War 1 soldiers with mixed European gear and a very bulky fantasy rifle that looks like it has a 'wheel lock' looking mechanism in the middle.
One of the soldiers in the trench in the beginning has an Short Magazine Lee Enfield (No1Mk.III) with a bayonet just before he is blown up by a mortar round.
MAC-11
Early on Lt. Maximillian von Steiner (Benno Fürmann) aims a highly modified MAC-11 pistol at Capt. Nathan Rooker (Sean Pertwee). Though it is decorated with science fiction add ons, it is clearly a MAC-11 as the base pistol.
Mauser Rifle
Heavily modified Mauser rifles are disguised as future weapons, however, the receivers and bolts are clearly visible. Most notably carried by Cpl. Valerie Duval(Devon Aoki) and Maj. 'Mitch' Hunter (Thomas Jane)
Fictional pistol
Major characters appear to hold a heavily customized pistol. It's hard to say if it is based on a real live firing pistol design since the gun fire seems to be all CGI and not blank fire in the film.
