mordekaiser with Jhin ghost (Gameplay)

I was playing mordekaiser and when I killed a jhin with my ult on him the ghost was stuck at fourth shot. So for the whole team fight is was fourth shot after fourth shot. It was not reloading. But after the fight and he was out-of-combat the ghost jhin finally reloaded so that's shows me he's suppose to reload. I'm not sure if this is suppose to happen bug it gives the team I big advantage since they have basically a better version of the adc they just had