Boltshot reload glitch
From Halopedia, the Halo wiki
The Boltshot reload glitch was a glitch that had been able to be performed in Halo 4 in War Games. It resulted in the rapid reloading of the Boltshot. It was patched in a Title Update on December 6, 2012.
In order to have performed this glitch, the player simply pressed the reload button immediately after they had fired the weapon. This caused the weapon to reload immediately, without going through the animation or cool-down period. This imparted an unfair advantage to the performer of this glitch, especially if they had the ammo Support upgrade equipped. Due to this, the glitch was patched. Fortunately, this glitch was only effective at close range, and the performer was vulnerable to ranged weapons.