Mark:

Thanks for the quick response. The manual I have for the gun says that the Max load for the .50 CAL is 100 gr. My dad mis-understood the weight conversion in the front of the manual which is why he was shooting 72 gr of powder. Looking at his notes, he didn't realize that using a powder measure by volume, 100 gr of Pyrodex RS is the same as 100 gr black powder. Not the same weight, but the same volume.

Looks like I'll start at 85 gr or so and get the new scope sighted in at 100 yards. Then I'll start going up in increments of 5 gr to see what gives me the best groups.

Should be fun! Now I just have to find a good range in my area.... I actually don't know of any![:@]