dalberg
by clean I mean clean of any teflon tape, nothing left on it.
Correct, that is what most often occurs. What that indictes to me is that you installed the tape correctly on the BP, insterted the BP into the breech and snugged the BP up to the barrel flange. Then as you shot the tape and BP installation seal all blow-bac from coming back down the or into the threads.
When you removed the BP the tape remained adheared to the threads of the barrel as you screwed the plug out. Which is not abnomal. In my Remingtons the tape usually does stay mostly on the plug, but in others it comes off and stays in the Breech plug threads.
This is what it might look like from my Remingtons..
Another example after shooting BH from the Remington
This is a plug getting ready to go into one of my Knights...
This picture shows the plug a little closer. One thing I would add, make sure you seat the tape on the plug. I do that by turning the plug in my fingers with the ratchet. While turning apply a small amount of pressure to the tape as it turns forcing the tape down into the threads of the plug.
I do not have a picture to show you but when the plug comes back out from my knights - most of the tape remains in the breech threads and can be easily removed with the bottle brush...
Hope some of this might help ya...