The CTG. you speak of, the 9.3x62 opened to .375 is virtualy identical to the .375/06IMP that Bevin King chambered up for me as well as to the original .375/06IMP I had back in the late 70's's, chambered by H.McGowen.
: Kick-ass ctg. it is, as mine is producing 2,845fps with 235Speers, 2,540fps with 285GS Speers and 2,470 with 300gr. bonded core Horandy's for safe max loads.
: When I picked up the 9.3 X62, I merely made a die to neck the .375/06 brass I had down to 9.3 and they chambered and headspaced perfectly.
: Taking 9.3x62 brass and necking up to .375 is one way of making them, as the base dia. of my chamber is .470", with a .460 shoulder, moved slightly forward of the '06, as is the 9.3's original chamber. Necking my formed cases down to take a .366" bullet and reducing the shoulder slightly, wil allow them to be chambered in a 9.3x62. My .375's brass is made by opening up '06 brass to .42", then necking down and placing the shoulder to headspace properly.
: I also found W748 was a good performer in the '06IMP .375, but the loads I ended up using 'sound' a bit high to publish here. I surmise the rifle I had was one of those annomolies that was able to use higher than normal loads. N202 also worked well.
: Scovil's .375 Hawk is a similar, but slightly smaller shoulder'd ctg than my present '06IMP.
: It is amazing when you can get 78 to 80gr. capacity from an '06 case. The Brown-Whelen case is similar.
: Your shorter 57mm case has also had an appeal to me for this 3/8" bore as most 57mm brass is usable.
: Your's, a 9.5X57R has a ratio of capacity to bore size for all North American Game, in a fairly easy shooting round.