????? 45/70 has been loaded with smokeless for many many moons now. Sounds more like a bore obstruction to me.
Until' you've seen what an UNDER Charge / Light load can do to a big case BPCR, I wouldn't go sideways into bore obstructions.
....AND,...the Pedersoli's are clearly marked "Black Powder Only"
Some of the early ones featured barrels of a leaded free machining steel, similar to a 12L14.
Hell, muzzle loading barrels wrought from that stuff have gone South.
GTC
