What would cause a line trace to deflect from the crosshairs?

So, no luck so far. I did some messing around (and I’m not 100% sure of what I did), and the hit markers are no longer drifting from the crosshairs. However, the line traces are now consistent in their offset. I am not great with vector math. It seems UE4 treats location data the same as unit directional data. And why do you suggest adding the initial vector (location) to the forward vector (directional)?
In my blueprint, I am now doing a forward vector trace from the player camera, finding the impact point, then calculating the ‘Look at Rotation’ from the gun barrel to the first impact point, and then converting that to a unit vector for the second line/sphere trace. Any and all help/input would be super welcome.

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