C Sharps 40-65 barrel questions...

I succumbed to an unfired, C Sharps 40-65 with a long range tang sight and interchangeable aperture front sight at a local pawnshop. It had been there a couple of years ago, disappeared, and reappeared two weeks ago. In the interim it acquired a new set of RCBS dies and a new Lyman mold. It was still unfired, the owner ran up against money problems and pawned it back. I got it for the price of the bare rifle. SN is 75-3xxx. Too bad he did not add a DST or SST.....;)
The round barrel is 30" tapered to 1" at the muzzle. It is an 8-groove, possibly a Badger but unmarked as to origin. It appeared to be gain twist, starting at 17 1/2 at the throat and ending at 18 1/2 twist at the muzzle. Anyone else have one like this? My brass is formed from 45/70. Rainy weather is good for black powder but it's been a bit ridiculous of late. Initial loading is 53 gr of Goex FFG, what I have on hand, with a Lyman 410665 bullet.Attachment 239302