I thought most revolving rifles used about 60 grains - but I dunno if this varied for big calibres.
Are you considering shooting a percussion revolving rifle? If so, I hope you've thought through the safety aspects. It's not for nothing that they never really caught on like the arm's length pistol, and AFAIK are not being repro'd currently .
Regards,
MikB
...history... is, indeed, little more than the register of the crimes, follies, and misfortunes of mankind. (Edward Gibbon: Decline and Fall of the Roman Empire)