It's incredibly hard and inconsistent to get precision hits on Vex with a bow. I see a year old posts about this topic and it's still there. Bows are normal agains any other enemy but vex you just can't hit drits with a bow.
Vex has bit Wonkyness in the hitbox with other weapons also but bows are just unusable. Go test it out, it's redicillous.
-
I’ve had no issues with hitting Crits on vex with a bow. Just aim for the juice box. It probably has more to do with the accuracy stat on the bow. Some bows just don’t shoot straight. It can also be an issue if you just genuinely hate the sight on the bow even if it makes the stats better. If you really like bows I would recommend trinity ghoul as number one with catalyst then le monarch. Arsenic bite and point of the stag are probably my favorite legendary bows. Whispering slab is okay but I personally don’t like the sight on it.