The ornamental design for a rimshock, as shown and described.
FIG. 1 is a perspective view of a rim shock;
FIG. 2 is a front elevational view thereof;
FIG. 3 is a rear elevational view thereof;
FIG. 4 is a top plan view thereof;
FIG. 5 is a bottom elevational view thereof;
FIG. 6 is a left-side elevational view thereof;
FIG. 7 is a right-side elevational view thereof; and,
FIG. 8 is a perspective view thereof.
The broken line showing of a plurality of wing nuts in FIGS. 1-8 and the broken line showing of a drum in FIG. 8 are included for the purpose of showing environmental structure and form no part of the claimed design.