No1Mk3 wrote: ... ... To take the mid point as a start is not unreasonable... ... ...
I hear what you are saying No1, but i believe unless you actually KNOW FOR SURE what result you will get, im a fan of starting lower...particularly in this case using heavier brass.
Im not arguing with you as it seems you know more than i...but I have made the 'assumption' my mid range load will be fine with my old 22-250 & had flattened primers & tight cases with some very snappy recoil...all from "assuming" (& being told by "seasoned experts"), a mid load will be fine with different brass...boy was i (& they) wrong.
That coupled with trying adi 308 brass in my 7-08 starting with loads under adi min, & hitting pressure (prob due to neck clearance best i can tell)...with this i was also told "you should be ok",...from these experiences i ALWAYS weigh my brass now, regardless...!!!, & if im unsure i start lower...or i only start mid point if using same brass & having used a similar proj in that rifle.
Obviously you have a thorough understanding of what his (the op) result may be, but he obviously doesnt, & i believe he is best advised that to start mid point with a heavier brass he has not used is not ness a the best idea.
Not arguing, just my opinion based on my own experiences.
Cheers
The man who knows everything, doesnt really know everything...he's just stopped learning...