SetRelativeRotation not working properly

I am having a problem with set relative rotation function. My commit is here.
What happens is that I get the appropriate value for elevation, but when I pass it to the SetRelativeRotation function, it does not work.

2017-05-05 13_05_08-New notification.png
The code of elevate function
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The output, barrel not moving at all.

Can’t see any obvious errors. So, question is if you’re taking into account the fact that FRotator arguments are in degrees. I imagine it could be hard to see that small change of 1.666 degrees (as per your example output log).

Yeah, the elevate function is ticking, so every frame the elevation is added. I guess there is a problem with SetRelativeRotation, but cannot figure out what it is.