[adweisbe]

I have been using Hornady one shot case lube and lubing sometimes hours in advance of when I will actually use the press. Today I tried a case I had lubed several days ago and it felt like it required more force then usual to size. Does the case lube evaporate over time?

[MNgoldenbear]

Not that I know of. The CARRIER (solvent) evaporates, but I don't think the lube has much of a vapor pressure. There should have still been a nice, thin -- but visible, layer of lube on the case. If the spray coverage was thin and spotty to begin with (hard to see right after applying because the carrier makes it look like there is an even coating), that may have caused your problem.