I'd personally surely try them. There is not rationale that they would not work just high-quality with your Beeman. I've experienced very good luck with RWS pellets in all of my airguns (Hatsan, Crossman, Benjamin and many others.). I'd personally try a tin and find out how your Grizzly likes https://super17722211.blogsumer.com/35135290/not-known-factual-statements-about-super177