Surprise Party Amumu's Q Hit Box Feels Off

So this season I've been playing Amumu almost exclusively to the point where I play him in 80 - 90% of my ranked matches. I started off this season playing Amumu without a skin and became really comfortable with the animation and the hit box of his q. The hit box is actually pretty big and it moves fast enough that the skill became relatively easy to hit. It was to the point where the size of the hit box would make me hit q's that I thought was going to miss. Recently, about a week ago, I bought the surprise party Amumu skin because I was playing the champ so much and why not. However, I gradually realized that either the hit box of Suprise party Amumu's q was smaller or the animation was not following the actual hit box. I don't know if that made much sense but something is definitely off about the skin's q. I'm not saying that the q is going through enemy champions and acting completely broken, but q's that normally hit on the no skin Amumu are not hitting on the Surprise Party Amumu. Please if anyone else feels the same way as I do about this skin's q please respond below or even if you feel that I am completely wrong please respond below so I can make sure I'm not going completely mad!!!! Thanks!

Side note - Maybe the no skin Amumu is the broken one with a larger than should be hit box? Riot please look into this!!