I was shooting some very good groups (about 1.5" at 100 yards) with my Disc Extremes using Two 50 grain Pellets of Triple Seven.

I then purchased another box of Triple Seven pellets, and both guns started spraying bullets -- five to six inch groups became the norm, using the same bullets and sabots, and shooting under similar weather conditions.

Has anyone ever experienced anything like this?

I purchased some loose Triple Seven ffg powder and shot by far the best groups I've ever shot, after experimenting of course.