I used 14.0 grains of Blue Dot under the Lyman #410610 for years, and never had a problem. I was getting about 1225 fps with that combination and accuracy was fine.

I don't have any idea why Blue Dot would be any more dangerous in one straight-walled revolver case than another, and it makes no sense to me at all. On the other hand, it also makes no sense to me that a powder manufacturer would discourage use of its product unnecessarily.

I don't have the answers, but I do have a jug of Blue Dot that will sit on the shelf until this thing clears up. There are other powders that work just as well---if not better---in my .41 Mag. That would be the one I wish to retain its structural integrity!