I don't have a pedersoli nor have I ever shot one, but I've seen a few causing ignition problems at the range. I've also seen some pictures of disassembled pedersoli breech plugs and it appears that the problem may be with the hole in the breech plug being too small. The breaching system seems to be similar to CVA/TRADITIONS but the cva and traditions have a larger hole in the plug.
So some have problems and some don't. It's probably a matter of how the shooter manages the gun and the wiping between shots regimen.
If I had one I'd be tempted to modify the breech so that hole would be more like a funnel but it wouldn't be the first time one of my ideas backfired.