Schmeisser's MP-18,I - The First True Submachine Gun
The MP-18,I is recognized as the first submachine gun to see combat, developed by Germany in late 1915 for trench clearing. It features a simple open-bolt, blowback-operated mechanism with full-auto fire only, lacking a disconnector. The design includes a Trommel magazine with a sleeve to prevent over-insertion, and early models bear distinct markings like 'M.P. 18,I.' and the year of manufacture.









