Anyway. I think the only reason someone would say a woman couldn't use a gun is because most prints and paintings of that time showed men as wielding them, not women, but there are records of a great many women that took up arms during conflict, including those that hid their gender to assist in wartimes. One such woman was Deborah Samson Gannet of Massachusetts who disguised herself as a young man in order to join the American Army. Another was Anna Maria Lane, who fought directly with Washington and his unit.
"Mulan" fables are quite common in ye olde times. Apparently, to preserve the honor of a crested family and having the main knight dad dead and no sons, a daughter or even a wife would don the armor and do some jousting and even straightforward battles, upon realizing this it was made a gesture of chivalry to lift up the visor of your helmet to friendly knights. Or well, one of the alleged reasons resulting to such a gesture (that was eventually transformed to tipping of a hat)
"Those women be making us manly men look bad HURDRHUR"