The guys that make them said to use low to mid-range jacketed data. Why would you not do that? Do these other reloaders ("everyone") that give different data know more than the manyfacturer?
In short, yes. Berry's has not tested their bullets in my gun, in my range environment. Load development is key, in MY situation, for example, accuracy was incredible at .5 off of max out a 6" GP100. I mean one of the most accurate load/gun combination I have ever witnessed. If Berrys says use low-mid range charges with their bullets, I dont blame them, everyone producing reloading supplies and equipment in a responsible manner will
recommend safety first, they have a business to protect.