I picked up an ’86 carbine with the long forend a couple of weeks ago, caliber .45-70 in the 17XXX range.  Minute traces of case color on the frame, most of the blue on barrel, excellent bore, mechanics and wood.  I’m looking for information that might lead to any surveys done on these particular carbines.  I know they are rare, but I’d like to have some idea as to how many were produced.  Any info would be greatly appreciated.  Thank you.