Shooting yesterday with .690+" (~14-bore, ~500grain) ball from Track.
Swiss 2f and 1.5f powder, 5-1/2 drams and the usual cup-shaped waxed card over-powder with lubricated wool felt wadding the rifle printed a bit higher on the target and slightly crossing, less vertical difference from Right/Left barrels. I think the rifle likes the better metallic gas seal of the slightly oversize ball (inside a .010" difference here)
Next time out it'll be more of this ball but a batch of them over 5 drams of Goex 2f and the same wadding.

The fouling from the Goex powder is much nicer - soft and wet from breech to muzzle and clean and consistent, the Swiss was flaky and hard. Since the rifle has enough case capacity for a good load on roundball with the Goex I'll be sticking with the red tin cans!
Also the next time out I'll likely have the chronograph running again.

Cheers
Tinker