Start with WW . Settle on a test media . Work a load . Shoot the test media at 25 and 25 yd past as far as you expect to shoot on game so 25&125 I guess if you get 125-150% of original dia at 125 and 75% or more of start weight in one piece at 25 you're done . If it doesn't then you adjust probably with pure lead and tin until it does .
The other option is to cast WW pick a 32/8mm with a 65% dia meplat and let em' rip .
I ran numbers for a new bullet in a new cartridge. We don't all agree on the best set of numbers to use , I fall back on 1000 ftlb at 100 yd because that was the minimum number that I had for 38 yr . I have an idea as to what alloys I need for a particular pressure window and impact speed . I don't care what a .170 FP 62 gr HP does after it hits , in the 222 it's going 2400 fps on departure and most likely a 50# dog is as big as the game is getting with it on purpose anyway. I use 75/24.5/.5 more or less WW/20-1/cu in the 6.8 and 7×6.8 SPC it doesn't expand but the .09 FP on the NOE leaves a 3/4" exit on a pithy pine log of 16-18" at 65 yd . That one meets the 1k@100 and I don't believe I'd rely on a catchers glove . 2200 MV 131.0 ready to load . Pithy pine ain't meat but it's it's wet pulp and not far off hit the offside shoulder and the Forest prince is certain to abdicate the throne .
This 7×57 with a 179 gr 7mm-168 SP and the NOE .278 BC says 1900 fps MV is plenty to reach the 1k@100 the alloy I chose is w/o cu and is hours after casting even water dropped soft . I went that way , 60/40 WW/roof jacks , because the long shot will be 100 yd maybe and I needed or thought I needed to fatten up the nose . I have about a .090 meplat after sizing and plenty of land contact . Long ago used the same alloy source metal for a 30 cal , not quite double dia , but near zero weight loss at 50 yd into powdered clay with a 1600 MV . The 8.5 twist and alloy just wouldn't go over 1800 and group in the 06' and 1600 is all I could get out of the x39 with the length restrictions. In any case close to double dia is a 1/2" hole through the pump and bellows space . My concern and it will be tested is that it'll splash instead of drill at 20 yd .
For a 30 cal I have the 311-165 RD with it's 70% meplat (or something close) 2000 fps MV is easy in 30-30 and 06' and I only need it to stay together long enough to get to the off side . It's almost a WC it's going to create a lot of damage whether it's "hydrostatic" shock or not . ACWW .
35 cal is the next step my The Load in a 358 Win is completely over kill for whitetail but I'd whack a bear or a 4-500# hog with confidence at 150-175 yd and only sweat the holdover about as long as it takes to break the sear . 35-250 @2100 fps WCWW + 10% purish or ACWW .
45 Colts 454424@1050 , 45 Raptor 350 gr basically a 458-340 Lee only .453-350 @1600 , or 45-70 with a 458193 or 45-500FN @1000-1100 . Yeah 50/50 works here the Colts held to 50 yd , the Raptor to 125 and the 45-70 to 200 primarily for hold over reasons with open sights . Expansion is available but with the pathetic 45 Colts capable of instant death on a calm 165# hog and a half inch hole cut in the exit shield after 26" and 2 ribs before it exited I feel pretty good about whatever alloy shoots well .
The upper end of these loads is 25 kpsi . Even the hot 222 and 6.8 are "only" about 42kpsi .
It's taken me most of 15 yr of digesting tomes , let alone volumes , of information and it's depressing to think about how many 1000s of rounds , and 100s of lbs of lead I've shot to get to this point .
Honestly you have reached the point of information load and book knowledge here and on CB and the book of faces where the only thing you can do to go any further is stuff some WW in a case and scrub it out of the barrel while you meditate on whether it was alloy or lube failure and what you need to fix to stop it .
The most valuable thing we can say now is ;
If it leads at the breach it ain't big enough.
If it leads at the muzzle it ain't got enough or the right lube .
If it leads in between there's a barrel effect like a roll stamp or choke .
Go load some 38 Special charges in 357 cases and work them up to full tilt 357 mag with Unique and a set of 50/50 and straight WW both water dropped . Do 5 each in about .3 gr steps with each alloy sized or not to a friction fit in the throats . You will learn volumes from this trial and volumes of what you've read will start to make sense .
"Sometimes you just have to throw away the book and fly the airplane" .