I would certainly check out them. There is not reason that they would not work just good inside your Beeman. I have had excellent luck with RWS pellets in all of my airguns (Hatsan, Crossman, Benjamin etc.). I'd try a tin and see how your Grizzly likes them as all https://super17789998.bleepblogs.com/36428359/super177-no-further-a-mystery