It is highly likely that your HRA's were all matching until the
CMP switched the parts around.
All correct rifles sold as a lesser grade have the parts mixed around. This is done when the rifles are disassembled for inspection. The guy at the bench is under direction to ensure than no lesser grade rifle leaves with all matching parts. The CMP swaps out the marked parts: bolts, operating rods, stocks, trigger guards. The amount of swapping depends. It is usually a minimum of two parts, but it can be all of the parts, in any random selection.
CMP deigns this, but I know people who may have worked there and they told me what was going on.