The MP40 is the successor to the MP38 and MP36; created out of machined steel. The weapon was not developed by MP18 designer Hugo Schmeisser; however Schmeisser did develope the magazine for the weapon. The weapon was known to be used by mostly the Wehrmacht, Gestapo and Luftwaffe; but also had limited use with the Schutzstaffel. The MP40 was also responsible for the creation of the STG-44.
To this very day the MP40 has been used by multiple countries and militaries.
By the year 2025, this weapon stopped being produced; however there was a variant called the MP25 that fired lasers.
The group of Nazis that created the Fascirians also utilized the MP40 as one of their main weapons. They are constantly manufactured in their war plants along with their ammunition and magazines; also modifications.