great bottle cleaning tip for stuff that hardened inside the bottle
 

My father told me to get some shot (bbs). when cleaning the bottles everyone
has run into that little bit of dried stuff in the bottle the brush cant
reach. put the shot in the bottle with water (cleaning solution) and start
swirling. It works great. It even works on the gallon jugs for the stuff
around the neck. Im just trying to give back for all the info you all have
given me.
Stephen