Joe,
This may be of some help to you. I found exactly the opposite situation in an 1863 Pocket. The situation is that I am in the process (long process) of rehabbing an 1863 Pocket Remington that I bought (in pieces) from one of the emanent scholars on this forum.
Unable to find ASM parts (its an ASM pistol) I had to resort to some stuff from Pietta most notably the hammer. This required a bit of fitting and filing just the get to the point where I could pull back the hammer with the trigger installed.
But once I had the hammer-trigger interface to the point at which it was at least free, I found that working the action smoothed the movement.
I don't know that this is good news. What it means is that cycling the hammer is changing the contours in a microscopic way. (Not rocket science, its called "wear") The fact that the smoothing of the action took place relatively quickly (only about fifty to one hundred operations of the hammer) tells me that in filing the parts I took off enough metal to get below the point at which the case hardening had its desired effect. At one or more points in the trigger or hammer or both, I got down to soft metal.
So now, unless I do some hardening, I can look forward to a shorter life of the action of this pistol. I guess I should have figured this might happen, but I only just started on this project and it is my first at home gunsmithing that is any more than just replacing springs or nipples or building kits.
I am a novice, but that does not seem to matter because when I offer comments there are plenty of smarter folks who come in an get me straight, So here goes:
The sources of roughness in my action was trigger to hammer contact surfaces. When I removed the interference and smoothed those surfaces the roughness went away. Obviously there are other contact surfaces which might be equally at fault.
You might examine those surfaces, probably with a magnifier, looking for roughness that can be shaped. I hope that others in the group who may endorse this idea will also inform us as to the best way to restore the hardness to the surface.
If it is wear from use that has cause the rough action, you might look for other places on the parts at which the case hardening has been worn away to shiney metal.
You might also see if simply replacing the hammer screw will set things right.