OP, I don't remember too much on the other thread, but if Berger bullets were involved, it is wise to test each bullet and verify that the tip is not clogged with polishing compound, or whatever it is they put in the tip.
Used to be that about 1/4 to 1/3 of Berger hunting bullets would actually have a clogged tip. You have to put a small pin in the tip to see if it is clogged or not. Report is that clogged Berger tips often don't expand, no matter range, from muzzle to infinity.
This has changed though since they relocated to AZ last year. New lots of Berger bullets from the AZ plant, no longer seem to have that problem. I have shot about 500 bullets from the AZ Berger plant and haven't found a clogged tip yet.
Could this have been your issue?