Call any Ballistics lab and ask about the random pressure excursions, the 243 and 7mm RM are the two worst offenders. That is repeatable, scientifically measurable, peer reviewed, fact.
Been shooting the 243 win for years. Tried a bunch of bullets from 80 to 105 grains from different manufacturers. Tested over 12 different powders. I've NEVER had any of these so-called pressure excursions.