Have you heard of a device called “auto sear”? You could hardly shoot a dose from a regular pistol. However, when this device is used, it is already possible. Auto sear can transform a semi automatic gun into a weapon capable of emptying an entire magazine with a single pull of the trigger. Auto sears are also known as switches or chips.
As it is difficult for many people to buy a submachine gun, the popularity of these devices has grown rapidly. They appeared on the market in the 70’s. These are small plastic or metal parts that are often sold on the black market. See in the video below what the car sear looks like and how you can use it to create the smallest submachine gun.