I took the Carcano 7RWH , Santa Barbara 98 358 Win , Savage 275 Rigby , and Dad's 700 25-06' out today.
The Carcano was not a complete failure. I had some 180 HP BT Match Kings , apparently they need that last half inch of twist . Groups did close some in spite of the 45° impacts. The 6.8 case just doesn't have the volume to go any faster . I wish I could some of the old Hornady 154 gr HPBTs for it .
While 18 rounds in a 4" circle at 50 isn't special I haven't shot this build much and have only the time spent on it with the 358 . It looks like the sizing is just a little bit small in the H&I die . I shot 20 to fire form formed 308 for the final trim . The PB 360-238 XCB and 8.5 gr of Unique was pretty tame but even loads that opened the inside the bow floor release we're just a firm push . Having moulds from 95-250 gr and an RB I suppose I could feed it something intended for a 380 ,9mm or 38/357 and load it as such .
The 275 likes the little bit of jump with the 7mm--168 . 8.5 Unique gave me a neat little 1.5" square . The 41&41.3 gr of the old DuPont marked 4350 made neat little 2.5" circles . I did get a little fouling at the muzzle about the last 2.5" . This is a new barrel with only maybe 200 rounds through it so the pores and stuff aren't really filled yet and it's all been cast save 10 rounds.
Dad's 25 did well with the first load behind the 125 gr 260-120 . If I never get a better group it's unlikely that anything coyote or up will go very far . Just 41.0 H4831 from fresh cans (circa 2015) . I don't know how fast they're getting there but it's likely something north of 2200 fps MV . The next step at 41.3 was a dinner plate , a surprise but not an unusual thing in my experience with fast twists.