FIG. 1 is an upper, right, front perspective view of the barrel chamber block, showing my new design;
FIG. 2 is an upper, left, front perspective view thereof;
FIG. 3 is an upper, right, rear perspective view thereof;
FIG. 4 is an upper, left, rear perspective view thereof;
FIG. 5 is a right side view thereof;
FIG. 6 is a left side view thereof;
FIG. 7 is a top plan view thereof;
FIG. 8 is a bottom plan view thereof;
FIG. 9 is a front view thereof; and,
FIG. 10 is a rear view thereof.
The broken lines showing portions of the barrel chamber block as well as the broken lines showing environmental structure form no part of the claimed design.