Re: Lyman deerstalker load
Some will venture to say you can go higher... I really wouldn't mess with anything higher than that.
But slowly work your way up from 70, even 2-5 grains at a time, shoot a three shot group, climb the ladder, etc. If you feel at any time that something didn't seem right when the thing ignites, stop and call it a day.
Some guns can be really picky. One man's max load is another's "play at the range" load.
I might head out this afternoon to burn some powder myself, and do the exact thing, climb a little.
Good luck and have fun with that rifle!
Shootin' Deers and Drinkin' Beers... That's How I Roll...