RE: one week til ml season opens and need to work up a new load
#1- yes, so long as you don't spill any. 1/4 lb = ~1750 grains weight
85 grains by volume of PyroPwill weigh roughly 75 grains (SWAG but probably very close)
1750/75 = ~23 loads
#2 - I really don't know how to respond but, since that is the charge you seem to have verified, yes - but limit your shots to 50 yards and aim for the center of the boiler room.