I may buy an antique "rifle". It is a percussion rifle. The owner said it was a fowler but has a .58 caliber rifled barrel liner. The liner seems to measure right at .58 on the grooves. The liner has a faint line at the muzzle but it is clean. ROT looks to be around 1:74. The nipple does come out although not sure of the thread. The hammer holds at half and full ****. The single trigger releases the hammer with around 3-pounds. Two rear sights, one fixed and a flip-up blade for the second distance. Front sight appears a square post. I don't have photos because it isn't mine yet but I have viewed the "rifle". Anything you can think of that I should be looking at or investigating? The original "fowler" ( I suppose ) is from around 1863 according to owner. The engraving seems to be re-cut, some bluing appears newer and the liner is very clean, hinting at recent upgrades. The owner purchased it from a known person but has never fired it. The known person is a beneficiary of the previous owner and has no information.