Bump fire

Bump firing is the act of using the recoil of a firearm with or without a stock to fire multiple rounds in rapid succession. This process is achieved by holding the firearm in a normal firing position, releasing the grip on the firing hand (leaving the trigger finger in its normal position), pushing the rifle forward in order to apply pressure on the trigger finger from the trigger, and keeping the trigger finger near the same position. Since the firearm will recoil against the shoulder and then return to its previous position after the round has been fired—thus pushing the trigger against the trigger finger again—large bursts can be fired.

The rapid bursts from semi-automatic firearms simulate the discharge of automatic firearms which were regulated and banned in America by the National Firearms Act and the Firearm Owners Protection Act, respectively. Even though a large number of rounds are fired in rapid succession, the trigger finger initiates each discharge; therefore, fully automatic fire is not actually taking place.

One method of "bump firing" is to hold the rifle with the off-hand (non-trigger hand) and instead of gripping it with the trigger hand, only inserting the forefinger in front of the trigger. In order to achieve the rapid fire succession, the shooter continuously pulls the rifle forward with the off-hand while holding the trigger finger stationary such that the trigger is pulled into the forefinger. The recoil will pull the rifle backwards as the off-hand pulls it forwards. A new round will be chambered before the weapon is pulled back into the stationary trigger finger.

Devices, such as Tac triggers, can greatly assist a person in bump firing a semi-automatic firearm. These triggers attach on to a firearm's trigger guard and put tension on the back of the trigger which forces it to rebound much more easily off a person's finger. An even simpler method, which works better with AR-15 rifles, is to use a rubber band and wrap it around the trigger guard. This works just as well as the Tac triggers but does not cost $40.00, as Tac triggers normally cost. With these devices a person can bump fire a firearm from almost any position just like a regular automatic firearm. However, not all devices that facilitate bump firing are legal. A famous example is the case of the Akins Accelerator for the Ruger 10/22. Though the Bureau of Alcohol, Tobacco, Firearms and Explosives (BATFE) initially allowed mechanical devices for producing rapid fire, this ruling has since been reversed and currently the device is illegal. [http://www.atf.gov/alcohol/info/revrule/rules/atfruling_2006-2.pdf]

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