I'll tell you what happens when you don't get a good cure on PC...it smears off in the barrel then gets cooked on by subsequent firings. My fault, I wasn't monitoring the temperature, only set the temp on oven and started baking after up to temp. The old oven couldn't maintain temp, and I didn't realize it. Bullets looked good, passed the smash test, but were not bonded well enough for shooting.
This is a terrible mess to clean up. I takes repeated soaking with Kroil, scrubbing with bronze brush, and scrubbing with Iosso bore paste. Eventually got things cleaned.
As advised on this forum, I bought a glass oven thermometer, and a new toaster oven. I watch the thermometer and make sure it is over 400 at all times while curing.
By the way, I found the toaster ovens with quartz elements heat up faster than the standard elements, and seem to hold temp at a more constant level.
If you suspect you have an under cured batch of pc bullets, you may want to re-consider before firing. Just wanted to pass this along.
Dan