After taking a closer look when I got home, I'm not entirely sure the difference from the crimp was quite the cure, though I think it did help reduce the granules a bit. However, I was shooting a different revolver, and I hadn't felt anything while shooting the last 100 rounds. That made me optimistic. But I got to thinking. When I said the timing was fine on the other revolver, I was basing that on the fact that lockup was assured before the hammer would fall on each chamber. I can easily advance the cylinder all the way around in a slow double action pull without ever dropping the hammer. I check this sort of thing regularly. But that test presumes that everything is lined up when it's locked up, and the revolver in question is a new one purchased early this year.
So I did a closer inspection of the alignment when the cylinder is locked on each hole, and I think in some cases I can see the right edge of the charge hole peeking in. It's not a large or obvious thing, but it may be enough to account for my experience with it. After reflecting on the matter, I can remember feeling a bit more debris coming back when I've shot other loads with it. I just never gave it much thought until it started happening almost every shot. I'm going to call S&W next week and see about sending it in.
So I did a closer inspection of the alignment when the cylinder is locked on each hole, and I think in some cases I can see the right edge of the charge hole peeking in. It's not a large or obvious thing, but it may be enough to account for my experience with it. After reflecting on the matter, I can remember feeling a bit more debris coming back when I've shot other loads with it. I just never gave it much thought until it started happening almost every shot. I'm going to call S&W next week and see about sending it in.