No way your patch was spitty enough to wet 40 gr. of powder. I slobber all over my patches when I detect a bit of fouling just above the charge on the previous shot; never had any kind of effect on my load that I could detect. Unless you have a patented breech, you shouldn't be able to get more than a couple of grains of powder down the flash hole. If you did, it was because the ball wasn't seated, and your powder charge was scattered loosely up the barrel, and didn't light up with the original flash. Dirty gun would be my guess; the ball jammed up a couple of inches up the barrel. If the previous owner was using greasy patches a lot, you may have to soak the breech area with soapy water for an hour or so to soften the asphalt-like fouling. Good luck with it.