To update, I did grab the secondhand rifle off Graeme Forbes.
I cast a bunch of .45 calibre balls and bullets yesterday for it as well as a pile of bullets for the .303.
And shot my first group with it this arvo.
Using .440" pure lead balls, .005" lubed patches and 50 grains of FFF black off the bench.
At fifty yards with a light breeze from three o'clock my first shot hit 3mm high and 32mm left of my point of aim at 1052fps from a clean barrel.
My next three shots fell into a neat 39mm triangle, 24mm left and 82mm high. Velocities were 1440fps, 1520fps and 2113fps! The ringing in my ears confirmed that last shot wasn't a false reading.
I moved the target out to 100 yards and a fifth shot dropped in 220mm low and 145mm left at 1444fps.
A sixth shot hit 152mm low and 21mm right of POI at 1837fps.
I had hoped to shoot groups with two different balls, different patch thicknesses and three different bullets at various charges to find the most accurate combination.
But it looks like barrel fouling is a major variable in this game
I'm going to have to set aside a lot of hours for load development that includes scrubbing the bore clean after every shot.
I can also see that I'm going to have mark the ramrod to ensure a consistent seating of the ball every time.
Overall though, tons of fun