Miss Fortune Q range increased by rapid fire cannon. Bug or intentionally?

When i was playing Miss Fortune for the first time I followed the recommend build list but when i bought rapid fire cannon noticed that it also increased the range of my q when it was fully charged. When i told my friends about this there was only 3 answers i got from them

1. That's not true you troll.
2. I didn't know about that.
3. It sounds like a bug. So can someone please tell me if it was coded like this intentionally by riot or is this a bug? I don't want to use this in game then get banned for abusing in game bugs/glitches like when you could buy blue trinket at level 1 instead of level 9 or when graves could have unlimited ammo.