So a few days ago I responded to a thread and I think I may be wrong in my thinking. I said I believe the brass sticks to the front of the chamber upon firing because of pressure and then the thick non expanding head of the case pushes to the bolt and stretches the case where the thin part of the case meets the head. Then I got to thinking about straight wall cases and revolvers vs bottleneck cases. Straight wall cases don't stretch much nor is there a problem with case head separation. It would take very little pressure to push the case to the bolt face. Maybe only 50 or 100psi, which is way below brass expanding to grab the chamber wall. If that is true, then we would get no stretching of straight cases and lots of stretch and blow out of high case capacity small bore cases. This would also account for why bottle neck cases don't work well in revolvers. At high pressure the steel of the gun expands a little and then retracts to it's original size where the brass expands to fit the expanded chamber but does not shrink back quite to it's original size and becomes hard to extract. This leads me to believe there is little problem with very small amounts of lube left on a case from sizing. If you put enough grease/oil on a round it would be possible for the oil to be forced forward ( around the neck area) as the case expanded to prevent the neck from expanding and raising pressure of the fired round. I believe bolt face pressure will be the same as the interior of the case whether the case is lubed or not. I know there are some of you out there that know a lot more about this than I so, am I guilty of fuzzy thinking or am I on the right track?