I have a problem that I just discovered with my Lyman 1858 Remmy. I haven't shot the revolver in a year or so and put it away in good order. Seems from full cock, if you fart on it, the hammer falls. A few times after noticing this, it seemed if the hammer was just falling off full cock on it's own. I measured the trigger with my triger pull gauge and it averaged 1 1/4 lbs. I don't remember it being this light. What could be causing this?