The slight case bulge is ok when loading cast bullets. It shows that the lead bullet is oversized. That is great thing with cast lead. If it chambers keep it like it is. As for the lead at the forcing cone sounds like too hard of an alloy to me. When bullets are hard it takes more to deform the base enough for a good seal to the bore. Softer alloys will get a better seal most times.
Oh and for the sake of saying so. Use a copper Chore Boy wrapped around a cleaning brush to get the lead out. If it is just a small amount there. After that find some softer lead to alloy what you have with. Try a little bit. Then shoot them and see.
No matter how many times you do it and nothing happens it only takes something going wrong one time to kill you.