Which of the following best describes a "run away gun"?

A "run away gun" refers to a situation where a firearm fires continuously, typically due to a malfunction in the firing mechanism or failure of some component. This scenario can occur in fully automatic weapons, where the weapon continues to discharge rounds without the trigger being engaged, often leading to uncontrollable firing. Such occurrences are dangerous and can result in unintended damage or injury.

The other descriptions do not accurately capture the essence of what constitutes a "run away gun." Misfiring guns, such as those that only discharge improperly or fail to operate, do not fit the continuous discharge aspect. A gun with a delayed response suggests that it takes time to fire after the trigger is pulled, which is not related to the runaway condition. Lastly, a gun with a faulty barrel would imply issues related to its structure or accuracy rather than a continuous firing issue. Thus, the definition that aligns most accurately with the term is one that refers to a gun that fires continuously.