1:8 will enable you to use and stabilise the heavier bullets 69,75,77,80. & 90 grain
N140 gives good results
Ball powders tend to meter consistently through most powder measures where as grain type not so consistently although the LEE perfect powder measure which uses a ‘wiper’ performs very well.
You may find seating the bullet off the lands 10-20 thou improves accuracy (you’ll have to try that out )
If a magazine fed rifle then watch out for over length(magazine) as they may not fit (to long) if set off from the lands .
Other than that a cracking round out to 600yds and beyond weather (wind ) permitting using the heavier bullets .

ATB
James