From Halopedia, the Halo wiki
|This article contains information about a non-canonical subject that, while official, is not part of the established Halo universe.|
The burst pistol is a deleted Forerunner weapon in Halo 4, present in the files for Spartan Ops. It is untextured and fires weak directed energy. It may have been an early version of the Boltshot, as it bears some similarity.