I've tried different charges but have always made sure there wasn't any space between powder wad and bullet. I may try using pyro P as I am now using pyrodex RG.
I have made my own lube for a trapdoor springfield and matched the diameter of the bullet to the groove diameter. .460 groove and a .462 cast bullet and it shot very well. I'm not sure lube is a factor due to the lack of build up after the fouling shot and the shallow grooves on the Italian copy, but will try my home made lube and see if there is a difference.
Thanks Gents and any other suggestions would be appreciated.