FIG. 1 is a perspective view of a gun screwdriver showing my design;

FIG. 2 is a front side view therefore;

FIG. 3 is a rear side view therefore;

FIG. 4 is a left side view thereof;

FIG. 5 is a right side view thereof;

FIG. 6 is a top view thereof;

FIG. 7 is a bottom view thereof; and,

FIG. 8 is a perspective view of a gun screwdriver when partially disassembled.

The broken line showing of environmental structure is for illustrative purposes only and forms no part of the claimed design.