The Gusenberg Sweeper is a weapon in Grand Theft Auto V and Grand Theft Auto Online, released as part of the time-limited Valentine's Day Massacre Special pack. It is based on the Thompson submachine gun, more commonly known by its nickname, the "Tommy Gun". The weapon has a 30 round magazine by default; however, a 50 round extended magazine is available. Even though the real world Thompson uses the .45 ACP cartridge, the Gusenberg Sweeper shares its ammunition with the Combat MG and the MG instead of the SMG and Micro-SMG.
- The 30-round and 50-round magazine uses the same drum magazine, even though 30-round box magazines do exist for the Thompson.