Cleaning Breech Plug - White Hots pellets

What is efficient in soaking/cleaning a breech plug; Optima V2 QRBP? Thanks!

I normally remove the BP and soak it in a small bottle of black powder solvent (not suitable for bh209) while I'm cleaning the bore and action. The i remove from solvent and scrub with a toothbrush, dry. Apply antisieze and install.
Remember to also remove your firing pin assembly and clean and oil it.

I do the same thing, but I also follow Lew’s advice and use either a can of compress air or my compressor and blow through the nipple to ensure it’s cleaned out and dried inside as well as the breech area where the nipple screws into.

Hot soapy water, even with. Bh209.  I use a plastic bristle brush and a tips. 1/8" drill bit down the flash channel.