All double are individuals I think. My SxS 9.3x74r will regulate good groups with both 232 bullets and 286 bullers. I believe it was regulated with the new Norma oryx 286s, but with the 286 norma alaskan's while the point of aim shifts a bit and the group opens up, its still a useful hunting group (2-3 1/2" at 100y), same with the 232 vulcans. Not a big deal to adjust the scope and she's ready to go.