The Gasser M1870 was a revolver chambered for 11.25x36mmR and was adopted by the Austro-Hungarian Cavalry in 1870. It was an open-frame model, with the barrel unit attached to the frame by a screw beneath the cylinder arbor. The arbor pin was screwed into the barrel unit and fitted into a recess in the standing breech. The cylinder was gate-loaded from the right side, and a rod ejector was carried beneath the barrel. The M1870 Gasser became the Austro-Hungarian cavalry revolver. Despite being outdated, it was liked among Austrian Storm troops during World War I for its stopping power.
— In-game description
The Gasser M1870 fills the role of high-damage, low rate-of-fire pistol for the Assault kit. The Gasser M1870 has one of the slower rates of fire among the revolvers, being faster than only the No. 3 Revolver. It makes up for this with a very high damage profile, being able to kill targets in two shots up to 22 meters away, and having the highest minimum damage, being able to kill targets in 5 shots or fewer at long ranges.
The Gasser is notable in that each cartridge has to be ejected and reloaded individually through a single port (comparable to the DAO-12 shotgun), rather than folding out the cylinder as most other revolvers do. This makes the reload for the weapon very long indeed, significantly longer than the Assault's other weapons, primary or secondary.
Unlike other revolvers, the player may hold downto automatically fire consecutive shots from the hip, guaranteeing its stated rate of fire. When aiming down sight, it fires in single-shot mode.