Having shot the 200gn Wildcats and the 189gn Caut's a lot in our big 7mm's in the Fatso family based on the necked down and improved 338 Lapua and 300 Norma brass, I think the 9" twist will be borderline if you want them to work from sealevel on up. The only 9" twist barrel that would stabilize the 200gn'ers at sealevel was a Kreiger. None of the button rifled barrels word stabilize them to 1000 yards. In a 30" Lilja, the 200's at 3300fps shot the tiniest groups ever at 600, but fell out of the sky before they got to the 1000 yard target board. The theory is that the cut rifled barrels are the true to twist rate, and the buttoned ones are always just a tad slower, and that certainly seemed to be the case from our testing. I know having spoken to Kirby a lot about this that he has no problem with them at his altitude with 9" twist Liljas, so its the thicker air at sealevel that's the problem. Now if these new Bergers are the same length as the 200gn Wildcats, then I don't believe you will reliably stabilize them out of 9" twists at sealevel either. I would suggest a 8.5" would be ideal at ours and Kirby's AM chambering's velocities, and an 8" in the WSM's etc - if you want them to work at sealevel. Even though we hunt up into many thousands of feet at least as high as you guys, we do our load developments at sealevel, and its a pain if the bullets don't make it to the target!
And to the jacket thickness, the thin jacket hunting 180gn Bergers won't work at all out of our 8" twist Broughtons at any sort of velocity. They will handle up to 3400fps out of 9" twists if you keep on top of your throats. The 8" twists worked superbly with the 200gn Wildcats at 3250 to 3300fps while Richard was making them, and also with the 189gn Caut's at 3375fps and the 175gn SMK's at 3475fps, and now we use the 180gn Hybrid exclusively in them at 3425fps. This bullet is so good at this velocity there hardly seems the need for another (did I really say that???
Anyway, my point is that it will be a real juggling act trying to get enough twist to stabilize the 195's while not over spinning their thin jackets. Hopefully it can be done, if not, just bring them out with the target jacket as with the 180gn Hybrid and I'll be very happy!
These things are killing really well for us, here's a Red stag we just shot a couple of days ago with the under 7lbs including March scope 7mm Fatmax pushing the Hybrid at 3250fps. He was sitting down 720 yards away slightly quartering towards us with only the top 4" of his shoulder visible. As it was getting dark, we decided to take the shot. Willie hit him in front of the nearside shoulder, high through the forward upper section of chest, and the fully expanded bullet ended up the the offside shoulder blade. It had shed over half its weight smashing bone, but had certainly expanded! I wish I knew how to post up a video, as you'll see the stag's head just drops, he doesn't move at all other than a few quivers!
Anyway, looking forward to testing these new 195's - Berger, you've done it again!