An interesting thread ... Way too much to it to type on this tiny phone out in the boonies , reception is hit or miss , LOL .... Reading old books , ledgers , manuscripts , they regularly pulled the breach plug for maintenance etc. Ive messed with originals 18 and early 19 th century and not only did they have loose tolerances from their age , obviously ,but they didnt have fine threads ... Johnathan Alder pulled the breech plug in his gun because he missed a wolf , a native superstition , and scrubbed the bore ....seemed strange but he did it out in the woods . Obviously back a couple hundred years ago they didnt want their guns blowing up but they sure didnt have to worry about liability law suits either ... The fine threads and tight fit on barrels today are pretty tough . I can unbreech some barrels in the field but the majority of them , even flat breech faced plugs , no ...they are just too tight . Nothing wrong with that from a safety perspective but a pain when unbreeching a barrel is needed. Many rendezvous there was a gunsmith present with bench , vice and tools but not all of them unfortunately . Even in my shop it can be quite a chore unbreeching a barrel ....and some ....just impossible . Pick your firearm wisely . I love my flat breech faced flintlock trade guns ...to each their own though .
