Jerry, Said it before Rorschac did not make a 7 ogive only an 8.5 I have Watsons, fowlers,rubright on a rorschac and about any other one all 8.5 this really shouldn't be this difficult if you feel the need to check just make a rad. gage. you do not need a comparator just a compass and some card board 8.5 x's .243 swing arc and cut lay next to bullet, make two a 7 and an 8.5 then get back with me..