While we're bringing back this old thread, I've been using Longshot for some 10 gauge loads. The thing I've found is, it seems like a go big or don't go at all powder for my purpose. For every load from my official books, it worked extremely well. The problem was, every load was a big magnum load, and every time I tried to step off the load even a bit, it would cause the pattern to go goofy, all over the place. At full charge, it sent out a heavy load at very high velocity with a very good pattern, and when you tried to tame it, it just fell all to pieces. I tried a load that was advertised at 1550 fps for a 1 1/2 lead birdshot load, and I believe without a doubt it was all of that velocity. When I backed it off to make it more palatable, it became useless.
Has anyone else had this kind of issue? Does it have a very narrow band of charge weights where it does work well, and where it doesn't?