During World War 2 (1939-1945), the German Army primarily relied on two mortar weapons at the infantry level - the compact 5cm (50mm) leGrW 36 and the larger 8cm (80mm) GrW 34 medium mortar (both detailed elsewhere on this site). Both were well-made weapons designed in the pre-war years (which lent themselves poorly to mass production in war time) but the 50mm form that soon showcased its inherent shortcomings after practical actions had been had - it was too complex for its own good, offered limited engagement range and its projectile was largely ineffective for the given role. Its lackluster field results led to production being halted as soon as 1941 and the weapon entered second-line duties soon after - though it managed an existence throughout the remainder of the war as ammunition supplies were readily available and portability was a strong quality for infantrymen.
Because of the increased reliance on the 8cm GrW 34 form, Rheinmetall engineers began work on a new version of this weapon in 1940. After the requisite prototyping, test and evaluation phases, the new product was adopted into service as the "kurzer 8cm Granatwerfer 42" series - in essence a lightweight version of the existing GrW 34 mortar while given a shortened barrel for compactness, weight-savings measures to reduce loads by half, and support for firing a heavier projectile of better anti-infantry performance. It held roughly the same engagement range as the 5cm lwGrW 36 before it. For transporting, the system could be broken down into three major components for reassembling at a new position by its multiple crew.
Production of the kz 8cm GrW 42 weapons began in 1941 and lasted until the end of the war in 1945. It garnered the nickname of "Stummelwerfer" ("Stump-Thrower") for its time in the field.
As completed, the Kz 8cm GrW 42 had a weight of 58.5 lb and its barrel measured 747mm long - making it an ideal weapon for issuance to German paratrooper elements in place of the leGrW 36 series. The weapon fired a 3.5 kilogram shell of 81.4mm caliber out to ranges of 1,100 meters. A trained and experienced crew could manage between 15 and 25 rounds per minute. Integrated into the weapon was an elevation function which allowed the barrel to be tilted at 40- to 90-degrees. Similarly, a traversing function allowed for 14- to 34-degrees turning along centerline to be achieved.