The first thing to try is warm soap water down the bore from the top. A wet patch normally pulls easier. The second thing to try is wrap the end of your rod, put it in a vise and pull on the barrel. As a last resort I have pulled the nipple and trickled in a couple grains of powder, put on a cap, and shot it out. Just a couple of grains or your going to be looking for your ramrod a long time. The first time I was very careful and the ramrod only came 1/2 way out, but that was good enough.