Here is a link telling how to load specific Pantone colors into Photoshop. The 185U and 186U colors are in the "Solid Uncoated" library. Neither of these colors gets the "out of gamut for printing" warning, but the 184U (fairly close to 185U) does. My guess is that the 185U is out of gamut for your printer's ink set, but that is just a SWAG.
Is your monitor calibrated? What printer, inkset and paper are you iusing? Are you using a profile for your specific printer, paper and ink? How was it generated? Are you using a "color aware" printing program (e.g. Photoshop, Qimage)? What "Rendering Intent" are you using?
This forum isn't really targeted at these types of problems, and you might also want to post your question at another forum that is more in tune with color management as it applies to printing.