Beware of old data; maximum loads and some less than max are often pretty hot. I have a Model 60 with a 12" twist. I have not been able to get good accuracy with heavy bullets.
Best luck has been with the Barnes 140 TSX BT (their tipped bullet did not shoot as well) and between 62-65 grains H4831. I'd call 65 a maximum load in my gun. The 145 Speer shoots just as well (groups from 3/4" - 1 1/4") using same powder weights as with the 140 Barnes. I use Federal 215 Magnum Match primers.
I assume your rifle is freebored, so bullets will need to be seated to a long OAL (perhaps as long as the magazine will handle) for best accuracy.
MY loads were worked up in Norma Super 7x61 brass of recent manufacture. If you're using original 7x61 brass (probably older than 1968) or reformed brass with less internal capacity than current Norma brass reduce powder charges accordingly.
