Gone and done it now. Loaded up my 1st batch of FFg black 45-70 rounds. Plan to participate (as opposed to compete) in a regional Buffalo Rifle match later this month. Tried out my homemade 30" drop tube on 65gr of Goex FFg compressed about 10% under a 20.1 alloy from a Lyman 457125 dropped at about 510gr. Launcher is a 34" barrel Uberti (Pedersoli) 1874 Sharps. Expect to learn much and take a lot of ribbing from the company assembled.
Oh and I remembered to make a blow tube also.
John