johnnyo

Personally I would start with a good cleaniong of the bore as already suggested - but I would skip the Hoppes #9 stuff and go right to JB's bore paste. It is a lot more effecient at cleaning the bore.... Hoppes will help maintain but I think you are beyond maintenance - you need to work on the bore.

One other thing I might suggest.... with a really good pin light look at the bottom of the QLA where the crown is and see if you have any material from the FPB shaved off and caught in that area... Since the crown is internal make sure you get that cleaned also...