Solothurn S-18 20mm Anti-Tank Rifle
The Solothurn S-18 series were a series of 20mm anti-tank rifles and anti-aircraft guns produced by Solothurn when the Swiss company was owned by Rheinmetall, in order to allow the latter to circumvent the manufacturing restrictions imposed on Germany after the First World War. They are all side-loading and downward-ejecting, and the infantry versions feed from detachable box magazines.
The initial variant was the S-18/100, firing a 20x105mmB (Solothurn Short) round. This variant was 69 inches long and weighed 99 pounds unloaded: it was adopted by Nazi Germany as the 20mm Tankbüchse Solothurn S18-100. An apparent subvariant, the S-18/154, was delivered to Finland, though it is not clear what the difference (if any) was between this and the standard 100. More clearly different was the S-18/350, a version redesigned for use as an aircraft cannon. The large curved box magazines were available in 5 or 10 round capacities with 10 being more common.
The S-18/1000 was a scaled-up version which fired the same 20x138mmB round used in the German 2cm FlaK 30 and 2cm FlaK 38 antiaircraft guns and the Finnish Lahti L-39 anti-tank gun. Firing such a ridiculously powerful round required the weapon to be enlarged in just about every way: it is 85 inches long and weighs in at 118 lbs unloaded. The recoil spring on this version is so powerful that a hand crank is used instead of the charging handle of the S-18/100, which is turned three times to cock the weapon, using a linkage which appears to be a repurposed bicycle chain. Like the S-18/100, it loads from a side-mounted 5 or 10 round curved magazine. The magazine well dimensions of the S-18/1000 were identical to those of the FlaK 30, meaning it could potentially also use the 20-round magazine for the latter.
The anti-aircraft gun version of the S-18/1000, the S-18/1100, is a recoil-operated select-fire weapon which was exclusively for mounted use.
The Solothurn S-18 20mm Anti-Tank Rifle and variants can be seen in the following films, television series, video games, and anime used by the following actors: