Why? U ax me why?
Conicals must obturate to form a full gas seal and do so consistently in order to be accurate. The deeper the grooves, the more likely a seal will either not be formed properlyor be blown during its course of travel through the bore. Cupped-base conicals would probably tend to do better in such barrels than the solid base boolits we generally shoot (in Whites). That is my understanding of such things - but it may really have more to do with magic.
I have some PRBullets Ultimate 1 conicals that did very well in my 700ML. I think their design is a little more forgiving of rifling depth than the bore-riding style ofconical typically used in Whites. I'll first have to determine bore dimensions to see if any of my ~.504 stuff even has a chance - if not, I'll bring the Ultimate 1s to the line.
At the rate I've been getting things done lately, don't look for any rapid revelations. [

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