Rich ’s post is very good, covering your specific issues.
New method:
Parenthetically, My 16 year old bicyclist and flintlock shooter suggested unloading our loaded moose rifle (60 cal) with a bike tire pump, since we couldn’t find the CO2 discharger after an unsuccessful day in the woods. So I took a basketball filling needle, ground off the side hole, giving it a flat end hole, held the needle against the vent, and he easily pumped the patched ball and powder right out the muzzle! The gently removed ball and patch got put right back into my loading block for our next try at a moose!
Bill Paton