I've still got about 200 357's that I tumble lubed and stored for a few months in the summer several years ago, I had just got my Loadmaster and ran off about 400 and shot the 1st 100 or so and went on to other loadings, well when I got back to the TL batch, they squibbed and upon pulling them; the powder was an oily cake, been pulling them a few at a time ever since. I use it in my 9mm, but I usually shoot all that I load in a week end and have never had a problem, although I do wipe the bottom of all the bullets to lessen the contamination.