I'm trying to calculate Northing Easting in QGIS. I can get it to calculate my lat/long using $y and $x in the field calculator. I changed coordinate systems to what I want it displayed at, but it's still calcing the lat/long
Do not use
Set CRS for Layer if you want to reproject your data. It changes only the CRS definition, but does not recalculate any coordinate.
So set it back to what it was before (WGS84 I assume), and use
Save As ... under a different name and different CRS.
Try saving a copy of the layer and when you get to the 'save as' menu, set the CRS there instead. I had similar issues and that worked for me, although it may be a bit of workaround more than a solution.