New member here, just saw your question about the case capacity of the 22 Savage Hi Power.
Page 118 of my 1987 copy of The Handloader's Manual of Cartridge Conversions by John J Donnelly shows 2.37 cc, or 36.70 g water.
The Improved version, with 24.54 degree shoulder angle per side, is on the next page, 2.70 cc, 41.70 g water.
The original parent case, 25-35 Win, with 8.93 shoulder angle (both sides), is 2.31 cc and 35.68 g water,
the 30-30 Win, 15.25 degrees per side is 2.88 cc, 44.50 g water.
Donnelly suggests using new 30-30 brass to re-form to the Hi Power case, probably because 25-35 brass is rarely available. No mention is made about the thickness of the reformed brass or the possibility that new 30-30 cases are built heavier to contain higher pressures than the OEM 25-35 brass.
The first reference book of case conversions that I am aware of was authored by Maj. George Nonte in the early 70s and is long out of print.
My more recent copy of Ken Howell's book of cartridge conversions is out on loan right now, but it is a worthwhile reference also. The sources may not agree on the numbers, however, depending on the method of measurement, but comparisons by percentage may be useful.
I hope this may offer you a little help in your calculations. Sounds interesting, please post your findings.