I use it in .40 S&W
My recollection is that it was originally designed for 7.62x25. I have not used it in that, but I have used a lot of it in the .40 S&W, and plan to use it in heavy bullet 9mm.
I like it because it fills up the case, such that a double charge will not fit in the case. Accuracy with cast Lead bullets is decent.
It does leave a sprinkling of unburned powder all over the bench, but the bore is clear.