Raycasting Bug? Or just classic Roblox API? FindPartOnRay

I'm trying to detect a part on a ray.

I create a part at mouse.Hit.p (blue)

(hand,mouse.Hit.P)*0,0,-range (green)

pos from FindPartOnRay (black)

The first two spawn correctly, the the pos from FindPartOnRay spawns almost randomly, as if the mouse was elsewhere. Wondering why.

Any help greatly appreciated.

Here are the examples of where pos is going for some reason: https://gyazo.com/60faffd95d875c24b8495f9f5bfeee5b

It was because I wasn't using mouse-targ.unit*range