Final answer:
A gun that continues to fire after the trigger is released is experiencing a malfunction, commonly due to a stuck trigger or mechanical fault. This situation does not relate to normal recoil, which is instead a result of Newton's third law of motion. Recoilless rifles minimize this effect by allowing gases to escape out the back end of the barrel.
Step-by-step explanation:
When a gun continues to fire after you release the trigger, this is often referred to as a malfunction such as "stuck trigger," "runaway gun," or "hammer follow." In firearms technology, each shot is usually supposed to correspond to a single pull of the trigger. Continuous firing after the trigger is released can be very dangerous and is typically the result of a mechanical fault.
The concept of recoil in guns is closely related to Newton's third law of motion, which states that for every action there is an equal and opposite reaction. In the context of firearms, when a bullet is expelled out of the barrel with a force in one direction, the gun itself is pushed back with an equal force. This rearward push is what we feel as the recoil or "kick" of the gun.
An ordinary rifle recoils because the force of the bullet being fired out one end of the barrel results in a backward force on the rifle itself. However, a recoilless rifle is designed with an open barrel at both ends, allowing some of the explosive force to escape out the back, which minimizes the recoil felt by the shooter. Still, standing close behind a recoilless rifle when it is fired is extremely unsafe due to the high-speed gases and potential debris expelled from the rear of the barrel.