Adam Brammer

It also doesn't have to be in a function, i tried with just command blocks and got the same bug

Still broken in the latest version

Have you tested this with simply /tp-ing? this might just be a bug regarding unloaded chunks.

It happens when I try to replicate it; your head slot has to be empty, and your hotbar and inventory have to have an empty space for it to work properly.

Turns out this also happens when the stack of pumpkins is in your off hand and in your inventory. (moves to the hotbar)

I tested it and the bow score works just fine, its only the arrows that don't count toward their scoreboards.