"I just finished off a keg of IMR4350 that could be 30 years old.I bought a new 1 pound can and loading 58 grains in a 30/06 the new powder came almost halfway up the neck."
I did the same thing with some older DuPont IMR 4831 with my .300 Weatherby. When I opened the new can of IMR brand 4831 it went halfway up the neck as well. I had to drop the charge by almost 5.0 full grains. Even if I hadn't caught it I would have been fine since I don't run things to the ragged edge. It pays to always check every time you open a new can. Bill T.