I recall reading the MauMau in Africa made shotguns (12ga) by wrapping Bamboo tubes with wet rawhide. These were fitted to a wood stock cut for a breech & fired with a rubberband cut from innertubes as I recall to power the firing pin made from a nail. I seem to recall reading about this at the time Winchester was introducing its fibeglass wrapped bbl.

Miller/TN
I Didn't Say Everything I Said, Yogi Berra