It's possible that someone entered the incorrect speling in they're machines' dictionary accidentally. Guage.
Nope, mine popped up as an error.
See attachment. I've done that with a few words and someday I'll figure out how to edit my dictionary to get rid of errors like that.
Now back to multi-barrel guns. WRT two barrels, I figure the best combo for around here would be .223 in the NATO chambering, 20 ga. on the bottom. Selectable by switch, single trigger, big hands, double triggers are not friendly to me. Don't know if that's mechanically possible, though, except for having a moveable firing pin on the hammer or a sliding action bar to have the hammer hit one or the other firing pin.