The ornamental design for a double-barreled bullpup pump-action shotgun, as shown and described.
FIG. 1 is an elevated right front perspective view of a double-barreled bullpup pump-action shotgun showing my (our) new design;
FIG. 2 is a left frontal perspective view thereof;
FIG. 3 is a right frontal perspective view thereof;
FIG. 4 is a lower right rear perspective view thereof;
FIG. 5 is a left elevation view thereof;
FIG. 6 is a right elevation view thereof;
FIG. 7 is a top view thereof;
FIG. 8 is a bottom view thereof;
FIG. 9 is a front elevation view thereof; and,
FIG. 10 is a rear elevation view thereof.
The broken line showing of aspects of the claimed design in FIGS. 1 through 10 is included for the purpose of illustrating environment and forms no part of the claimed design.