I have a nice 20P and decided to load a different bullet. I wanted to seat it into the lands And then back off and kept sticking a bullet in the barrel. I kept back the bullet off and finally blacked .bullet and instead instead of showing lands I got a solid ring around the bullet. I bought a bore scope and it looks like a washer between he case mouth and the leade which is black also. So it seems the washer looking ring is.preventing the bullet from reaching the lands. I've been loading for 60 years and never had this happen before.
Any suggestions to repair and prevent.
Any suggestions to repair and prevent.