Question: When was the gun invented that chambered the same .45 round as the M3 submachine gun?
Sentence (from "Thompson submachine gun"): The Thompson submachine gun was also known informally as the "Tommy Gun", "Annihilator", "Chicago Typewriter", "Chicago Piano", "Chicago Style", "Chicago Organ Grinder", "Trench Broom", "Trench Sweeper", "The Chopper", and simply "The Thompson".
Relevant evidence: No