maxman001: I wonder if you set the caliper's dial to "0" after attaching the gage to the caliper's jaw? Was the right gage for caliber used, and the caliper readjusted to the "0" mark?

Just read and follow the directions. You must be doing something wrong or your gun has an awfully long throat. The use of a comparator is pretty straight foward IMHO.

Geronimo