Wasn’t he the one who loaded his coach gun with rolls of shaved dimes?
That was one of the stories about Bob Olinger who was one of the deputies guarding Billy.
He (Olinger) supposedly bragged to Billy that he had loaded his shotgun with dimes, and threatened him (Billy) with it a few times trying to scare him. Billy ended up shooting Olinger with his own shotgun during the escape ... but probably with lead buckshot...the “Dimes” story is probably not true.
A 10 Ga with a full load of dimes in those days was probably a week’s salary for Olinger. and as firearms experimenters have proven since, dimes make a pretty poor shotgun load.