Well I did go to the range today to try out the new toy.
Results were better than I expected. The top group is using the 680 grain CBE Paradox HP projectile, with a load of Nobels 82, a shotgun powder I have left over from my Clay Target days and a BPI gas seal and various card and felt wads, then a liquid alox lubed bullet, roll crimped. That group measures 1.750" c to c of the widest holes.
The bottom group is 5 rounds of a .732" round ball, also liquid aloxed. The load for it uses AP 70N powder and a BPI Light Brush wad with the ball seated on top and a normal fold crimp applied, a very basic easy to load round. That group measures 2.300" c to c widest holes. Both groups were fired only at 50 metres. I fired 10 rounds at 100m with the CBE bullets offhand and managed to keep all of them in about a 7" circle, not bad, but not brilliant either.
Velocity went 1115 fps for the CBE bullets, unfortunately my chronograph did not want to co-operate with the round ball loads, most probably because of the wad producing error readings. All in all, I'm happy with it.

Regards,
David