There are a lot of variables to be controlled in reloading, the brand of primer is just one, and it's not generally the one at fault when a load is going astray. I've even done some experiments using different primers in the same load, anticipating primer shortages, and I generally find very little difference downrange between CCI, Remington, and Winchester (haven't tried Federal). For the most part, none of the loads I've developed reflect "maximums" listed in the manuals, in many cases I'm at least a grain under. But these loads are through MY rifles, under MY conditions, and using MY trigger finger. Your results may differ.