Long Bow Cancel?

I saw a person the other day shooting a longbow 3 times faster then my short bow i ask how he was doing it and they said it was long bow cancel now i looked it up what it says to do is press F5 with W plus left mouse button. i have tried and tried i cant fig out with longbow but i can semi get it to work with shortbow but its alot of buttons to be spammin so i was wondering if there is another way of doing it other then switching button config.

F5 cancelling is only with shortbow.

Long bow canceling uses a secondary weapon that makes the blue, charging bar come up.