NOT KNOWN FACTUAL STATEMENTS ABOUT SUPER177

I'd personally definitely try them. There's not cause that they would not function just high-quality as part of your Beeman. I've had excellent luck with RWS pellets in all of my airguns (Hatsan, Crossman, Benjamin and so forth.). I'd try a tin and find out how your Grizzly likes them as all guns appear to have their favored pellets.Umarex twelve G