Quickload gives pressures for loadings of powders under specific bullets, which you must enter for a calculation.
So does Sierra's software.
I load for a 1920s combination gun in 8x57JRS, an 1888 Commission Mauser in 8x57I (.318 bore), and several 8x57JR military rifles and sporting rifles. There are quite a few hunters here with 8x57JRS drillings, so all you need to do is ask for loads or load suggestions for specific bullets or weights and / or powders.
Norma has loads of the 8x57IR and 8x57IRS online, downloadable as PDF files.
www.norma.cc/en/Ammunition-Academy/Loading-Data/8x57-JRS
Reloading Data;
8x57 JRS; Download pdf
The IR loads are about at the starting loads for the 8x57 Mauser modern bolt action loads.
VV also has loads for the 8x57IRS online in its downloadable data.
http://www.vihtavuori.com/en/reloading-data/rifle-reloading/8-x-57-irs.html
The Lee load data which comes with their dies gives pressures for starting and max loads with all kinds of powders, and factors for estimating what the MV and pressures will be at reductions from maximum loads. If you don't use Lee Dies, I can scan that data sheet and send it to you.
What bullets are you wanting to shoot, and what powders do you have at your disposal?