Evolution of the Sturmgewehr: MP43/1, MP43, MP44, and StG44

MP43/1: https://jamesdjulia.com/item/52359-1-397/
MP44: https://jamesdjulia.com/item/52520-5-397/
StG44: https://jamesdjulia.com/item/52725-1-397/

Today we are going to look at the evolution of the Sturmgewehr – from the MP43/I and MP43 to the MP44 and StG44, what actually changed and why?