Well we've put the 585HE in #1s and 77s.
Work great. But I'd also try to get others like CZ and many others we've used, to do it.
As for 375s from our case, for extreme range the singleshot Lawtons and Stillers and similiar are the best
I just took Mitch over two boxes of cases, as he is building a bunch of the long range gun packages for guys.
Some on their actions and other actions..Ed
Ed, Do you know what the .375's are using for twist? Also, that looks like a 30"+ barrel. Must be using some sllooowww powder.
Ed