I'd personally definitely try them. There's not cause that they might not do the job just fine in your Beeman. I've experienced superior luck with RWS pellets in all of my airguns (Hatsan, Crossman, Benjamin etcetera.). I'd try out a tin and see how your Grizzly likes them as all guns appear to have their most loved pellets.Umarex 12 Gram CO2 is cl